Jason wakes up in the back of a school bus holding a girls hand. He doesn’t know her and can’t remember who he is. Another boy, Leo, joins in their conversation. Jason admits he doesn’t know either of them. The girl, Piper, is worried about him and thinks he might have a concussion. They explain he is on a field trip with the Wilderness School - a school for delinquent children. Coach Hedge gives them instructions about completing their worksheets. Leo asks him to use his megaphone. When Hedge does, he gets odd sounds (Leo’s doing). They arrive at the museum and go inside. Piper is paired with a guy named Jason. Leo is paired with Jason. As they walk through the museum, some of the other girls make fun of Piper for her Native American heritage. She ignores them. Jason wants to do something, but Leo warns him that Piper doesn’t like them fighting her battles. When they get outside to the sky walk, Coach Hedge sets them to completing their worksheets. Jason goes to the Coach to tell him he doesn’t remember anything and doesn’t belong there. The coach admits he has never seen him before that day. He thinks Jason is very powerful with the mist and most likely a half-blood. He says there are two others there he has to watch as well. There was supposed to be a package that is going to be picked up and Hedge wonders if that is Jason. There is a storm just above where they are and it starts getting intense. Hedge orders everyone back inside.
Dylan reveals he is a ventus - a storm spirit - and kicks up the winds to hurricane levels. He uses the wind to knock Leo off of the sky walk and into the grand canyon. Coach Hedge takes off his cap and shoes to reveal that he is a satyr. He goes after Leo, who is holding on to the wall of the massive chasm. Dylan admits he has known about Piper and Leo for a while, but held out until Jason arrived. He shoots electricity at Jason and Jason loses a shoe. Dylan is surprised when Jason gets up; still alive. Jason pulls the coin out of his pocket and flips it into the air so it becomes a completely golden sword. He takes out all the venti surrounding them except for Dylan. Hedge returns carrying Leo back up from the canyon. Dylan says his Mistress is calling him back and intends to take Jason with him. Piper tackles Dylan from behind and ends up being thrown over the edge of the canyon. Dylan decides to take half-conscious Leo instead of Jason. Hedge charges at Dylan to rescue Leo and shouts for Jason to go after Piper. Coach Hedge disappears with Dylan. Jason launches himself off the cliff and quickly catches up with Piper. He grabs her and gets ready to die. Suddenly, he realizes they are floating. The air supports him and he is able to launch them out of the canyon. When they get to the top, they check on Leo. Annabeth and Butch arrive in a chariot for their extraction to camp. Annabeth is disappointed the boy with one shoe she was sent to find is Jason and not her boyfriend, Percy Jackson, who has been missing for three days.
Piper, Jason and Leo join Annabeth and Butch on their chariot to go to Camp Half-Blood where they will be safe. On the way, Annabeth explains who they are. When the storm spirits start to gather to attack, Butch has the Pegasi make a jump and they arrive over the camp. Their wheels are gone and they end. Up crashing into the lake. They are pulled out quickly and the water nymphs get the destroyed chariot out of the water. Leo is quickly claimed by Hephaestus. Annabeth sends Jason with Drew to the big house to meet Chiron. She seems over pleased with herself for being able to spend separate Piper and Jason. Piper knows they will be enemies. Annabeth offers to show Piper around the camp.
Piper can tell that Annabeth is distracted while they walk around the camp. High up on the hill, Annabeth starts showing Piper all of the different cabins and explaining which gods children live in each one. Piper is a bit distracted herself. She had a dream that told her if she didn’t do what she was told, they would kill her father and make her pay painfully with everything. Piper tries to focus on not making friends. Annabeth tells her that Jason really did just show up at her school that day, but the mist is making her thing otherwise. Piper is disturbed that her vivid memories of getting to know and date Jason were fake. They stop by the weapons shed and Piper ends up picking out a dagger that belonged to Helen of Troy. When she takes it out of its sheath, she sees an image matching the voice in her dream. She drops it in her fear, but is able to convince Annabeth she is okay and still wants the dagger. As they go on, Annabeth tells her the big three - Zeus, Poseidon, and Hades - made a pact not to have any more demigod children, but mess up sometimes. They walk by the cabins and none feel like home to Piper. When they get to Zeus and Hera’s cabins, she notices there are footprints in the dust leading into Heras. Annabeth is reluctant to go in, but Piper strolls right in. She knows right away that she doesn’t like Hera. Rachel, the oracle, is there and Annabeth introduces them. Just as Piper is about to confess about her dream, Rachel grabs her. She tells her to free her by the solstice or the death will swallow them. “The fiery one is only the first. Bow to his will, and their king shall rise, dooming us all.”
Will Solace shows Leo around the camp. As they come to the cabins, Leo sees his old babysitter, Tia Callida, who tried to kill him when he was five. They end up at Cabin Nine, where the Hephaestus kids live. Jake Mason, the cabin’s Counselor since Charles Beckendorf died, is in a full body cast in his bunk. He asks Leo if he believes in ghosts or curses. Leo lies and says that he doesn’t. Jake assigns him Beckendorf’s old bunk and tells him there is a private room underneath. Leo takes a minute to explore all of the gadgets and features of his new bunk. Jake promises him Beckendorf didn’t die in the bed before he draws his camouflage curtain to get some sleep.
The last stop on Leo’s tour is the forges. He is impressed with his half-siblings and their projects, but none of them are functioning properly. He ends up getting needles in his shirt from a centaur-like bug killing machine that goes haywire and has to be smashed. A girl named Nyssa takes over the tour. She explains there is a dragon that the previous occupants of Cabin Nine had created. Beckendorf got it working and under control, but now that he is dead, it roams free and terrorizes the camp. Jake tried to control it, but ended up in the body cast. Leo asks if children are resistant to fire since he is the god of forge and fire. She explains it is very rare and dangerous for a demigod to have that ability. When they all go to dinner, Leo asks to stay behind for a few minutes to take it all in. He does something he hasn’t allowed himself to do since the accident that killed his mother. His fingers tingle and fire crawls across his palm.
Jason arrives at the Big House with Drew. She is impressed with him, but she makes him feel uncomfortable. When Chiron comes out to meet them, he mentions that Jason is supposed to be dead. The centaur sends Drew on her way and invites Jason in for lemonade. He wants to tell Jason what he knows, but he has sworn an oath that he will not. He notices Jason is referring to the gods by their Roman names and starts speaking to him in Latin. Jason answers in the same language. A dark mist pours out of the mouth of a stuffed leopard Dionysus brought to life. Jason grabs his coin and quickly flips it in the air to turn it into a sword. A woman appears saying she is his patron because his father gave him to her. It has taken her a month to be able to contact him. She needs Jason to free her from her prison and promises she will return his memories when he does. When she goes away, Chiron finishes his sentence. Jason explains what happened when time was frozen and asks Chiron to tell him what is going on. Rachel and Annabeth come in carrying Piper.
Chiron makes sure Piper is still alive and Annabeth goes to get the medical kit. Rachel explains the message that came through her to Piper and says it is not the same as when the Oracle of Delphi speaks through her. Jason asks if Piper was also asked to free the woman from her prison and Rachel confirms. They determine that Hera/Juno is the one that came to them. Chiron reaffirms he is not able to help them on this, but confirms it is bad news. He leaves them to decide what to do next. Rachel stays to watch over Piper while Annabeth takes Jason to Cabin Fifteen for the children of Hypnos. The cabin is filled with beds. They wake up a boy named Clovis. He tries to help Jason recover his memories, but tells him since they were stolen by a god, only that god could give them back. When Jason mentions freeing Juno, Clovis points out that the gods change when they take different forms. The Roman versions are much more war oriented. The fact that Juno rather than Hera appeared to Jason could mean something. Annabeth is starting to think Jason is in a lot of trouble.
Piper dreams about surfing with her father. She is waiting to tell him about stealing the BMW until after their day together is over. He barely has time for her and taking the car was her attempt at getting his attention. She asks about her mother and he tells her about the Ghost Country out west his father told him about. He doesn’t know where her mother is, but he knows he will never see her again. His assistant, Jane arrives and tells him about Piper stealing the car. He tells Piper she is going to a special school in Nevada to keep the dealership from pressing charges. The dream turns and the fiery giant, Enceladus, warns her that if she doesn’t do what he says, he will eat her father. When Piper wakes up, Rachel is there with her. She explains that Jason had a vision similar to hers and she thinks they are meant to work together. She tries to reassure Piper that everything will work out, but Piper isn’t so sure. The sound of a conch horn signals it is time for the campfire to start.
At the campfire, there are about fifty demigods and Chiron gathered around. The flames change with the crowds emotions. Annabeth tells everyone she didn’t find Percy, but did bring back new campers. Drew asks if the Great Prophecy has started. Rachel confirms that it has. Seven demigods, an oath, and death are all mentioned. Jason knows the prophecy in latin. Since Jason is the one that got the vision from Hera, it is his quest. They know they must free Hera by the winter solstice which is the next time the gods will gather. Chiron points out that Jason was claimed by Zeus long ago. He flips his coin and this time it lands on tails and becomes a spear that shoots lightning. Rachel gives him a prophecy saying he will need help from the forge and the dove. Nyssa volunteers to go with Jason on his question, but Leo knows it is his duty and promises a ride. Drew offers to fill the role of the dove, but Piper insists. She uses her powers of persuasion to convince most of the crowd. She is made over quickly and claimed by Aphrodite.
Leo leaves everyone at the fire and starts into the woods. He remembers Tia Callida and now knows she was Hera. She put him into a fireplace to sleep as a baby. He dreamt of a flying boat until his mother came home and pulled him out. She would put him through small trials to initiate his training so he could be the hero she would need. She gave him a knife to learn blades and a rattle snake to learn bravery. When he was five, he burned an inch deep imprint of his hands into a picnic table at his apartment complex. His mom tells him not to play with fire until he meets his father. When he was eight, he went to the machine shop with his mother. As they are leaving, she realizes she forgot her keys and goes back for them. Leo is locked in the break room. A woman in a shifting dirt dress appears saying she is going to kill his mom to dampen his spirit. She warns him to remember that day when he is asked to fight against her. Leo uses his fire to try to protect her, but loses consciousness instead. When he wakes up, the shop is burned down and the paramedics tell him his mother didn’t make it out. The police are suspicious of him because they know the fire started where he was. When the social workers take him to his relatives, they send him away saying he has a demon inside him. He goes through foster families, but always ends up running. Now he knows he has to go on the quest with Jason. Since they need to avoid the earth as the prophecy warned and he doesn’t have time to build the flying boat yet, Leo is going after the dragon in the woods.
Using his flame to navigate through the woods, Leo finds one of the traps the Hephaestus cabin set up to catch the dragon. He starts to inspect in and finds there is motor oil and tabasco sauce as bate and a large net that is meant to hold the dragon. Leo tests out the trap, but his weight isn’t enough to set it off. He gets to the middle of the trap before he realizes the dragon has snuck up on him. It shoots flames at Leo, but he isn’t hurt. He tries to convince it not to come after him because it will trap them both, but the dragon doesn’t listen. With the dragon in the net, Leo is able to get to the circuit board and finds a dirty disc. He cleans it as best he can, but knows it still needs work. When he releases the dragon, it has him get on its back. They go through the woods until they come to a door in the cliff. Leo is able to open it and finds Cabin 9’s abandoned bunker. He sees a drawing of plans for the flying ship from his dream. The dragon (Leo names Festus) curls up on the pad it was most likely created in and points to the ceiling. Leo sees they have a lot of work to do.
Jason dreams of being in a burnt mansion with wolves. The she-wolf, Lupa, tells him this is where he started his journey and he needs to find his way back. While the wolves do not care for Hera/Juno, they know it will be much worse for all if she is not freed.
Zeus’ cabin feels cold and unwelcoming to Jason. He can’t help feeling like he doesn’t belong there. The giant statue of his father in the middle of the room seems to be staring down at him. He sees a bed roll and some pictures over in the corner where the eyes of the statue can’t seem to reach. He looks at the pictures of Annabeth, Luke, and Thalia. Annabeth comes in and he asks her again if she wants to join them on his quest. She says she can’t. He can tell she knows more about the quest than she is saying. She warns him that it is usually better for heroes to learn about their quests in their own time. She does advise him to follow the monsters: the god of the north wind: Boreas, who is in Quebec, Canada. She sees him looking at the pictures and tells him that Thalia was a daughter of Zeus, but is now one of Artemis’ hunters. Something about Thalia seems familiar. He asks what her last name was. While Thalia hardly used a last name, when she did, she used her mothers: Grace. Jason makes Annabeth swear to keep a secret before he reveals his revelations. She agrees and he tells her Thalia is his sister.
Piper wakes up in the cabin ten and can’t get rid of the blessing from Aphrodite. Drew announces that Piper can help a boy named Mitchel with trash duty. Mitchel uses the opportunity to welcome Piper. He admits he got the worst chore because he told Drew that Piper might not be so bad. A young girl named Lacey brings her a backpack of supplies she collected from their cabin mates for her quest. Mitchel explains Drew is their cabin counselor because she is the oldest member since Selina died in the Titan War. Drew comes over to tell Piper that Selina was a traitor and implies that Piper is too. She insists Piper’s dad must be trash, but Piper reveals her father is Tristan McLean, a famous movie star. Everyone is curious if Piper has gone through her “right of passage” as a daughter of Aphrodite - break someone’s heart on purpose. Piper thinks this is an awful tradition. She tells them all that Drew is a dictator and they need to think for themselves. She believes there is more to being a child of Aphrodite, but isn’t able to define it before she leaves them.
Outside of the cabin, Leo arrives with Festus. Everyone is shocked or hiding in fear. Jason, Annabeth, and Nyssa come right up to them. Leo doesn’t tell them about the deserted bunker and says he found everything he needed in the woods. Annabeth is impressed and thinks it is a good omen for their quest. Jason and Piper confirm they are ready to go. Leo shows them how the dragon was built for riding and they take off. Piper sees Jason looking at a picture of Thalia and wonders who she is.
As they continue to fly north in search of Boreas, the three heroes go over their plans. Jason tells them they need to find Boreas, find the venti, and free Hera. He tells them about his dream with Lupa the wolf. Piper reminds them the prophecy mentions giants; after the first Titan War, the giants attacked Mount Olympus. Leo tells them about Tia Callida (Hera) and how he saw her at camp. Leaving out the fact that he has fire abilities, Leo tells them about his mom’s death. Leo isn’t sure freeing Hera and causing deaths is the best plan, but they are all sure it is better than the deaths that would occur if they don’t free the goddess. Piper promises not to let Leo fall of Festus so he can sleep while they travel to Quebec.
Leo wakes up as the sun is starting to set and they have reached Quebec. Two Boreads, Calais and Zethes come up to them to destroy them for not having air clearance. Piper is able to convince them it is an emergency landing. They lead them to the tower of a hotel in a castle. The entire place is covered in ice and they want the dragon deactivated for safety. Leo presses a button and Festus folds up into a very heavy suitcase. They still smell fire on Leo and insist he stays behind. Jason and Piper look to Leo for a decision, but he assures them he will be fine waiting for them there. When Jason tells them his name and that he is a son of Zeus, the Boreads wonder if he is the same Jason as the first one (even though they know he died a mortal death a long time ago). The girl leads Jason and Piper to go meet the king, Boreas.
Jason is thinking about Thalia as they walk up the stairs to go meet Boreas. He wonders how they are related. Piper is with him and he takes her hand to reassure her they will be fine. When the girl, Khione goddess of snow, sees this, she freezes their hands to make them let go of each other. They get to the throne room and Khione leads them in, saying she will be translating for them.
Boreas introduces himself, but before Khione can translate, Piper speaks back to him in French (all children of Aphrodite can speak French because it is the language of love). Khione is annoyed, but Boreas is impressed and starts speaking to them in English. He says they have orders to kill all demigods because he boss, Aeolus, hates them. However, he knows that Jason is a son of Zeus and he was told to listen to him before passing judgement. Piper tells their story since the Grand Canyon. Boreas gets a glimpse of Jason’s tattoo and it seems to influence his decision. He transforms into his Roman form, Aquilon, and says it is odd that Jason ended up at Camp Half-Blood. He thinks Jason will provide them entertainment and the demigods will rip each other apart. He reveals the storm spirits they are seeking are in Chicago. If they bring them to Aeolus, he will help them find Hera. He implies the person that holds Hera and the storm spirits mistress are different people. Zethes escorts them out and Leo has Festus ready for them to leave.
The demigods fly towards Chicago and Leo hands out sandwiches for each of them. Piper wonders what he is hiding since he was the only one the Boreads could smell fire on. She knows she is hiding her own secrets, so she doesn’t press the matter. She remembers camping in her Grandpa Tom’s front yard after he died. Her dad had planned to go there to fix it up in order to sell it, but decided to keep it instead. She asked him why he never played Native American roles and he says it is too close to home. Piper falls asleep and dreams of her father’s captor. He says he has learned patients from being trapped under a mountain. He shows her where he is and tells her to bring Jason and Leo to him so he can kill them. Piper becomes determined to rescue her father without betraying her friends. She wakes up and is falling through the air.
Jason is able to catch up to Piper and has her grab onto him. They race down to where Leo is also falling through the air. Jason is able to slow down there fall some, but they end up crash landing on top of a factory and fall through the roof. Piper lands on the catwalk and ends up breaking her ankle. Leo goes off to find Festus and find out what happened. Jason wants to stay with her, but they hear something and she sends him after Leo. When she hears a voice that sounds like Jason looking for her, Piper gets worried. She stops concerning herself with how much ambrosia she can eat without burning herself up and ends up eating the whole bar. Her ankle starts to heal quicker, but not quick enough for her to get away from the Cyclops that was impersonating Jason’s voice.
Leo finds Festus has landed on a line of portable toilets. He gets to work and finds the disc in the dragon’s brain has frozen over. This is the one piece he didn’t want to break because he isn’t sure how to fix it. He remembers his mother saying nothing is so broken it can’t be fixed, so he sets to work on it. The Earth woman appears in the chemicals and tells him to leave his friends to die. Leo hears the clashing of metal and rushes in to help his friends with a hammer he summons from his magical tool belt.
Leo gets back into the factory to find Piper and an unconscious Jason are being hung over a cooking fire in preparation for a spit. Two Cyclopses, Torque and Sump, are watching the demigods. Piper tries to charm-speak them into letting her and Jason go, but the third Cyclopes, Ma Gadget, their mother, tells them what Piper is trying to do and brings them back to their own minds. The large mother Cyclops sends Sump to get her salsa to put on her heroes as she eats them. She orders Jason to be killed first since he is about to die anyway. Leo sneaks around the warehouse rigging the large machinery arms so they will work with his universal remote. He uses the first one to throw Torque into the air and dust floats down indicating he has died. Sump returns with the salsa and Leo uses the next arm to hit him so hard he also turns to dust. Ma Gadget rips the arms apart, taking away Leo’s weapons. She throws some coals at him and then a barrel of kerosene, but Leo is not affected. He gets her to step under the large engine that is being suspended above and then uses his fire to break the weak link in the chain that is holding it up. She dies when it lands. Leo is weakened from the effort of concentrating the fire. He is able to get Piper and Jason down, but they have to leave in a hurry because the dust is starting to collect back into the Cyclopses bodies. Part of the prophecy that Tartarus wouldn’t hold monsters and Hades wouldn’t be able to hold souls.
Hera appears to Jason in a dream. Zeus thinks they might be able to avoid the upcoming conflict by not being as involved in the lives of humans and demigods. Hera heard a voice telling her to go to where she was captured. She admits she has fallen for this trap before and still went. She warns Jason he will face his worst enemy in Chicago and might be killed by her. Hera shows him she is unable to escape and weakening. Jason wakes up on Festus and Piper tells him what he missed out on. He feels awful for leaving his friends to defeat the Cyclopses by themselves. Leo tells them about seeing the Earth Woman’s face in the sludge outside the factory. When they are over Chicago, they spot a ventus.
The three heroes follow the ventus to the Crown Fountain where there are a group of Venti that go down the drain. They follow and decide the relatively dry location is a good place to rest. Leo uses his pack and magic tool belt to make them tacos. Jason asks if Piper’s dad is in trouble, but she tells him she can’t talk about it. After they eat, Piper falls asleep with her head in Jason’s lap. Jason tries to reassure Leo that he wasn’t responsible for his mother’s death. He tells Leo to get some sleep. When they are all rested, they decide to follow a draft south. They come to elevator doors that lead to a magical department store. They decide to start at the top floor. From there they spot Coach Hedge in a cage down on the first floor and decide they need to rescue him. Before they can start, a well polished woman calling herself a princess appears and asks if she can help them. Jason introduces them and she seems to glow oddly for a second before agreeing to help them.
Piper wants to attack the woman, but Jason and Leo seem to be under her charm-speak spell. Piper is too scared to use her own charm-speak to convince them the woman is evil. She follows as the woman leads the boys through the store showing them different products. She shows them a potion that can cure any ailment. It could possibly restore Jason’s memory, so Piper has interest in it. She asks the price and the woman tries to charm-speak her into agreeing to pay anything for it. Piper is able to resist. She tries to convince her friends to leave again, but they are still under the spell.
While the princess is showing Leo a forge that can be used to make weapons of imperial gold (like Jason’s sword), Piper tries to convince Jason that the woman, Medea, is dangerous. Medea has Jason and Leo start fighting each other while she uses a diamond to send an Iris message to Jane (Piper’s dad’s assistant). Jane was manipulated into helping with the capture of Piper’s dad. Medea agrees to let him go if Piper allows Jason and Leo to kill each other. She refuses. She is able to get both boys’ attention and explains Medea helped the original Jason steal the golden fleece from her family. She ran away with him, had two children with him, but he left her to marry a king’s daughter in Corinth. Medea killed her own children and Jason’s new bride to get back at him. Medea releases the sun dragons she used to escape Corinth and starts back up the escalators. Piper follows the witch while the boys fight the dragons. When they get to the top floor with the potions, Piper throws a shield at Medea and spills several of them. Leo calls out for help and Festus comes crashing through the roof to save them. The dragons get locked back in their hidden kennels. Piper is able to escape Medea by jumping off the edge where Jason and Leo catch her so they can escape on the bronze dragon. They fly away and the department store explodes.
Festus is starting to show signs of wear, but Leo keeps him going to make sure Medea isn’t trying to follow them. They start heading in the direction of San Diego, even though Medea told Piper the boys would die in the Bay Area. They know they have to find Aeolus because he is the one that knows where they need to go. Jason points out the wind trail Festus has been following, but Piper and Leo can’t see it. Jason takes the reigns so Leo can get some sleep. Hephaestus appears in Leo’s dream using his cold war broadcaster. He explains the gods are ashamed because they were saved by their demigod children. They were especially upset about Percy Jackson turning down their offer to become immortal. Zeus has closed down Olympus in hopes that staying quiet will calm down the Earth’s rising giants, but Hephaestus and several other gods don’t agree. Leo is a big part of uniting everyone to fight what is coming. Hephaestus is on the verge of being caught communicating and Leo wakes up. Jason and Piper are screaming as Festus is going down.
Leo tells Jason to get Piper off Festus so he can land and hopefully salvage him. The dragon is cold and he isn’t able to get to the control panel while they are in the air. He finds a snow covered lawn that is nicely lit and decides that will be the best place to land. As they fly over, a laser hits them and Leo blacks out. When he wakes up, Festus is in pieces. The cages he was carrying are in tact. He goes over to the dragon’s head who gives him a message in morse code. Leo makes him a promise before he dies. Leo asks Hephaestus to take Festus’ head back to the bunker and it disappears. Jason and Piper are confused, but Leo says he will explain later. He throws a piece of metal into the air and the lasers incinerate it. Since they cannot fly out of the gated yard, they decide they will have to go into the white mansion to find their way out.
There are several traps on the way through the yard and to the mansion that Leo has to deactivate. When they get to the door, it is unlocked. Leo checks for traps, but doesn’t find any. They all agree to bring the cages inside and stay there until morning. When they are all settled, Jason apologizes to Leo for what he said in Chicago when he was under Medea’s spell. Leo blows it off, knowing they are still friends. Jason goes to sleep while Leo works on unlocking Coach Hedge’s cage. Jason and Piper wake up to Coach Hedge waking up and screaming. They explain their quest to him and how they found him. He believes they found him for a reason. An old man walks in wearing his bathrobe and calls for his son, Lit.
Coach Hedge immediately goes to attack the stranger, but Jason convinces him to stop and sends the satyr outside. The old man is Midas, which shocks the three young heroes since he has been dead for centuries. Piper recalls the story saying Midas gave up the magic touch Diyonisous gave him because he turned his daughter to a gold statue. He takes her backpack and turns it to gold to prove he still has the touch. Leo is able to use the newly magical bag to put the storm spirits into for easier transport. Midas points out a statue of a girl and says that is his daughter. He admits he has turned his son to gold a few times, but they use the nearby river to turn him back. When the demigods try to leave, Midas quickly turns Piper and Leo into statues. Jason takes the option to fight Lit rather than be turned to gold. Jason uses his javelin to defend himself and finds out Lit doesn’t have any defensive moves. He is able to knock Lit onto Midas’ throne and then tells Midas he will have to help him up. Midas touches his shoulder and Lit is turned to gold. Jason summons lightning to blow the roof off the mansion and trap Midas under a chandelier. Rain comes pouring in that the gold starts to fade away. Jason covers Lit with a blanket hoping that will give the victims time to escape. Jason calls for Coach Hedge to grab Leo while he carries Piper away from the mansion.
When Piper wakes up, she is in a cave with her friends and Leo is keeping a fire going. Jason explains it took a bit longer than Leo to get her turned back from gold. He harnessed the storm spirits to get them away from the mansion, and he followed the trail to a mountain, Pikes Peak, in Colorado. Coach Hedge says Aeolus’ place is most likely anchored above them. Leo tells them about the conversation he had with his father, Hephaestus. Piper remembers her dad telling her the story of her name. There was a Cherokee woman who killed the king of the rattlesnakes because it was too close to her children. Rather than going to war, the husband sacrificed the woman to the snakes. Now whenever a Cherokee sings the snake song, rattlesnakes will not bite them. Piper decides to tell her friends about her dad being held captive by Enceladus. They discern that Enceladus is trying to lure them to the Bay Area to rather than letting them get to where Hera is being kept. They all agree that it is a trap and they need to focus on freeing Hera. Even if they did go to the Bay Area to rescue Piper’s dad, Enceladus would likely not let Piper live either because she is one of the seven demigods from the prophecy.
Wolves start howling and shortly after arrive at the cave. The king of the werewolves is bitter towards Jason because Zeus is the one that killed his fifty sons and turned him into a wolf. Piper remembers the story and that Zeus did that because Lycaon tried to feed him human flesh. The wolf admits he cannot kill Jason because someone else has already claimed the privilege (Piper wonders if it is Medea already reformed). Leo throws gas at them and then uses fire until he is worn out. Piper tries to stand and pulls out her dagger. Just as the wolves are getting ready to attack, silver arrows start piercing them. They run away with a group of Artemis’ hunters chasing after them. One hunter stays behind the check on them. Piper asks if her name is Thalia. She removes her hood. Jason tells her he is her brother.
Thalia asks Leo and Coach Hedge to take Piper outside so another hunter, Phoebe, can heal her. Jason asks Leo to stay with him and Leo agrees to it. Thalia tells Jason that their mother was a television actress and became an alcoholic. Zeus came back to her for a little while, but seemed to be a completely different person. He left again soon after. Jason was born and Hera insisted on his name. Thalia would take care of him. When Jason was two, they went out for a picnic and their mom asked Thalia to get something out of the car. When she got back to them, Jason was gone. Their mother said he might as well be dead. Thalia never told anyone about her little brother. A white wolf comes to the door and signals for Thalia. She says she has to get ready to go before she looses the trail of her fellow hunters. She agrees to help Jason get to Aeolus fortress first.
Outside the cave, Phoebe has set up a tent with a heater to heal Piper. Thalia sends Piper ahead while she takes the others to the misty ice bridge that leads to the fortress. Leo asks why a bridge is needed if the residents can fly. Thalia points out they need to be grounded to Earth sometimes, like now. Leo realizes that Hera called Jason a bridge. He thinks Jason is the key to bridging the gap between Camp Half Blood and the kids that wear the purple shirts. He gets so excited about the idea that he starts melting the bridge. Jason and Leo are able to make it across the bridge, but Thalia has to go back. She tells them to go save Piper’s dad. She and the hunters will go to the other wolves and Hera and hold them until Jason and his friends can get there to rescue the goddess. Jason says he doesn’t know where the other wolves are, but Thalia tells him he does.
Even though he knows it isn’t fair, Jason feels resentment toward Thalia because she never came looking for him. She has a new life for herself and he doesn’t remember anything. The group makes their way into the fortress where the yard is divided into four seasons. Coach Hedge wanders off to go eat some grass in the spring time part. Millie, an aura, meets them and agrees to take them to meet Aeolus.
Aeolus is in a control room and watches several screens, reads paper airplane messages, and seems to be directing the airwaves of Olympus’ own weather channel. There isn’t a floor around him and harpies have to be called to have a path made for their group. Aeolus agrees to meet with the demigods because he thinks they are there to discuss his contract with Olympus. He wants to be a god, not just master of the winds. He goes on air and tries to predict the weather based on what the gods are doing at the moment, but everything changes so quickly. When he returns, Jason explains they brought him his rouge storm spirits. He asks for the wind master’s help. Aeolus is not happy Jason is back for help a second time. Piper explains they only need to know the location of Enceladus so they can save her father and Hera. Aeolus gives her a picture of her and her father and Leo’s childhood drawing of his ship to Leo (he gets all things that are lost in the wind). Aphrodite and Hephaestus both tell Aeolus to help them. The wind master tells them Enceladus is just east of the San Francisco Bay. Coach Hedge joins them and Mellie is taken by him. Aeolus gets another message from the Earth woman and he decides they must die. They are knocked off the floor and fall into the chasm. Mellie uses her robes and has Jason help her land them in one of the below tunnels. She helps them escape, but they are flung into the air so hard that Jason is knocked out.
Piper dreams that she is on the roof of the Wilderness school with Jason watching a meteor shower. She asks him to dance and they do so without music. They kiss and she smiles. Aphrodite breaks into Piper’s dream. Piper is shocked that she remembers something so vividly that never happened. Her mother explains it is because Piper is her daughter and can see future possibilities. Aphrodite admits she is the oldest Olympian. When Kronos cut up his father Ouranos with his scythe and the pieces fell into the ocean, Aphrodite was born from the foam created. When the Titans were defeated, Gaea created the giants to eliminate Olympus. The only hope the Olympians have now is to have the two sides unite the seven greatest living demigods. Piper will be the mediator for the group once they all come together because she is the daughter of Aphrodite, who’s son Aeleas left to start the Roman Empire in Italy after the Trojan war. The goddess gives Piper a vial of liquid to give to her father to erase his memories of what happened to him. Piper doesn’t agree with it at first, but remembers him saying he would go crazy if he though it was all true. Aphrodite sends her daughter back to reality.
Piper and her friends wake up in a cafe with new clothes (Jason was barely changed) on and she has cash in her pocket. They order food and discuss their next steps. Leo has the drawing of the ship in the pocket of his new clothes, but he assures the others that is for later. Coach Hedge tells the story about Gaea having 12 Titan children with Ouranos and then convincing their son, Kronos, to kill him. Since Gaea is so large, it is difficult for her to stay awake, but if they don’t rescue Hera, she will awake and life as they know it will end. Piper doesn’t want to send her friends into a trap, but they are willing to go.
The demigods and Coach Hedge take a taxi as far up the mountain as they can. When they get out, Leo notices the car is sinking into the Earth and so are they. He pays the driver and tells him to get out of there as quickly as possible. They make their way to the top of Mount Diablo and Jason points out the surrounding cities like he knows the area well. At the top, Enceladus has a bonfire, large construction machinery, and Piper’s dad tied to a stake. Coach Hedge suggests the boys distract the giant while Piper saves her dad. They all look to Jason and he agrees it is the best plan they have.
Coach Hedge is knocked out almost instantly. Leo is able to get a wind up device he made on the walk up into a bulldozer before Enceladus spots Piper. The giant raises six Earthborn ogre-like monsters from the ground. He tells them Piper’s dad is Jason so they go after him. Jason goes after Enceladus. Leo gets to the harvester and is able to use the blades to kill three of the Earthborn. They form rocks from the dirt and take out the machine. Leo calls on dozer and the machine comes to life to protect Piper while she gets her dad free. It kills two ogres before they destroy it. The last Earthborn rushes after Piper and Leo shoves a screwdriver into its forehead. What that doesn’t stop it, Piper kills it with her knife. They immediately go to help Jason.
Jason fights Enceladus by himself. He tries to use speed to out maneuver the giant, but with Gaea using the earth to hold down his feet and aid Enceladus, Jason is not making any progress. Enceladus says Jason is the one that lead the assault on Mount Othrys against Krios and toppled the black throne. Jason doesn’t know what he is talking about (sounds like what Percy did). He tries to focus and fake out the giant, but his spear ends up shattered. Jason is too shocked to move quickly enough to completely avoid the giant’s fire breath.
Leo uses some remaining equipment to fire an ax at Enceladus. It sticks in his chest, but he quickly starts healing. However, he has fallen into the pit and the demigods are joined on the high ground. The giant isn’t worried about them defeating him because he knows it will take a god working together with a demigod to bring him down. Piper uses her Charm-speak on the giant to distract him while Jason leaps toward him for an attack. While on Enceladus’ head, Jason prays to his dad for help. A storm rolls in and Lighting is channelled through Jason to the giant. The ground is split and Enceladus hangs over the ledge of a chasm. He tells them his siblings are much worse than him before he falls in. The ground stops trying to pull them in and Gaea is back to sleeping for now. Coach Hedge wakes up and thinks that he defeated all the monsters. The demigods can’t help but laugh at his behavior. The mountain side is on fire and a helicopter is nearby to report on it. They decide that will be their way out.
Piper charm-speaks the helicopter pilot into flying them to the Oakland airport. Jason and Leo get her dad, Tristan, on board. Hedge gathers their supplies and they take off. On the way, Piper explains that Aphrodite is her mom and the reset of their adventure. Tristan is proud that she is an actual hero. Jason is interested in the Caldecott Tunnel on Highway 24 as they fly over it.
They land on the tarmac at the Oakland airport and have Tristan’s private jet brought over. Piper says she needs to get her dad home, but he insists that she finish the quest with her friends. Hedge agrees to go with him and make sure he is okay. Piper gives her dad the vial from Aphrodite. She tells her father to take it and they will discuss Piper’s true identity someday when he is ready. He does and Coach Hedge gets him on the plane. An Iris message appears from Thalia says they have found Hera, but must defeat her captors by sundown. She gives Jason clues about where the Wolf House is and Jason determines they need to go to Sonoma Valley. Rather than taking the pilot into battle with them, the demigods agree that Leo will drive the helicopter.
Jason tells them the Wolf House is the mansion Jack London built on sacred ground where his journey started. The land is cursed. Leo and Piper have similar thoughts about Jason not being the friend they have grown to know since the Wilderness school when he gets his memories back, but they don’t think he will betray them.
There is an ice storm when they arrive at Mount Diablo. Leo is just able to land and jump out of the helicopter before it is destroyed by a giant snowball. Thalia finds them, but has to use her last arrow to take out an Earthborn. She goes back to fighting while the other three demigods go inside. They find the pool with the two spires on either end with Hera in one of them. Leo sees her as he always has: Tia Callida. He isn’t happy about freeing her, but he knows it is better than the alternative. If Porphyrion rises, she will refuse to marry him and Gaea will rise. Leo remembers the line of the prophecy telling that fire and the dove will open the cage. Khione comes in with Thalia frozen into a statue. Jason gets ready to fight while Leo and Piper will work on the cage.
Jason’s memories start flooding back to him. Khione is confident the three demigods cannot thwart her plans, so she explains that she is on Gaea’s side. The realize she is the one that froze the dragon’s wires above Detroit and has been whispering to people to encourage them to follow her directions. She plans to kill Piper and Leo and make it look like Jason did it. Jason knows this will be effective in setting demigods against each other. Khione is going to take the places of power and Leo realizes this means Greece. She offers him to switch to her side, but he laughs at her. He minions charge and the demigods get ready to fight.
Jason jumps on the back of one of the horse-shaped venti and wills it to obey him. When he realizes its name is Tempest, the horse seems to appreciate him. Together they are able to take out the other storm spirits. Piper is able to charm speak the Earthborn enough to kill them with her dagger. Leo uses his fire to scare off Khione. Hera’s cage is filing up with dirt, so Leo tells her to talk to it and lull it back to sleep. He pulls out a circular saw and Tempest uses its electricity to power it. While they work on freeing Hera from the cage, Porphyrion wakes up and starts fighting Jason. The demigod is able to pull a sword from the giant’s hair and stick it in his ear. A flash of lighting makes the blow more effective. However, Porphyrion was made to destroy Zeus. Hera is freed before the giant can land his killing blow. Porphyrion disappears into the ground. Hera warns the demigods to avert their eyes as she kills the surrounding monsters, but Jason is too tired to think.
Piper holds Jason unsure whether or not he is alive. Thalia wants Hera to bring him back, but Hera cannot. Piper feels Jason breath and calls him back. He wakes up and they give him ambrosia to heal him. Thalia and Hera continue to bicker until Piper points out they will have to work together in the future. Leo points out that Porphyrion isn’t dead. Their fight is far from over. Thalia takes off with her hunters and promises Jason they will see each other again soon. Hera admits the Grace family is the first to have children from both the Greek and Roman sides. It is typical for Roman children to be taken from their parents early and made to survive trials. Afterwards, they go to a different place than Camp Half-Blood. Jason wants to know where that is, but Hera says he will find it when the time is right. They are all frustrated with cryptic messages from the gods, but Hera knows she cannot tell them too much because they have to make their own paths. Hera whisks them back to Camp Half-Blood and they land in the middle of the Aphrodite dinning table. Everyone is shocked to see them.
After telling their story and answering questions, Chiron sends the three heroes to bed. When Piper wakes up in the morning, Drew is standing over her and making demands. Piper gets up and challenges Drew for the counselor position of the Aphrodite cabin. Drew starts to make a fuss, but Piper pulls out her dagger and offers to duel right there. Drew steps down from her position and the rest of the cabin cheers. Before Drew leaves to tell Chiron why they are late to breakfast, Piper warns Drew that Jason is hers. Later that day, Piper is able to use the computer to video chat with her dad. Coach Hedge is taking care of him and has hired Mellie as his new assistant. She is pleased that he makes more than 30 seconds for her; even if it isn’t much more than that, it is a start. Piper finds Jason after a workout. He wants to tell her something, but he says it would be best for her to find out at the meeting that night when Rachel and Annabeth are there. Piper knows their paths are meant to be together for a while and she decides she can be patient. They agree to go meet Leo for his big reveal in the woods.
Leo reveals his is a fire user and opens the door to the bunker. The Hephaestus cabin mates are impressed with the level of technology in the bunker. Leo greets the head of Festus. There is a map from the Civil War and they all wonder what that means. Chiron, who promised not to speak of the last civil war amongst demigods starts telling. Human history tends to correspond with demigod history. The American Civil War and the last demigod civil war were both devastating. The gods separated the two sides and took extreme measures to make sure they didn’t know about each other. He thinks the bunker attracts misfortune and so did not bring up its existence during the recent Titan War. Leo thinks that isn’t the case. He pulls out the drawing Aeolus returned to him and points out its matching blueprints on the bulletin board. He knows he is meant to build the flying ship, the Argo II using Festus’ head as the mast. That is what the seven demigods in the prophecy will use to keep Porphyrion from destroying the original Mount Olympus in Greece and fully waking Gaea.
Chiron tells them they will need to have the war ship completed. They will need to leave by the summer solstice to be able to get to Greece in time. Jake Mason nominates Leo as their new lead counselor and all the Hephaestus cabin mates agree. He accepts.
Jason talks to the statue of Zeus in Cabin One. He knows his dad can’t come see him like the other godly parents do. Hera appears and tells him they needed to exchange leaders between the camps to bring them together. They need the seven greatest demigods of the age and currently, they are split between the two camps. Since the giants can only be defeated by a god and a demigod working together, they must be united. Hera disappears when Piper comes to get Jason for the meeting
There is a council meeting for the leaders of each cabin. Rachel and Annabeth are there, but Thalia is not. Jason tells their story. He explains there is another camp of demigods near San Francisco for the children of the gods in their Roman form. They two camps are kept separate because of their rivalry. When they meet on quests, the gods intervene and erase memories. Annabeth asks to go with them when the Argo II is complete. Jason thinks they need her because Percy Jackson was the one that was exchanged for Jason. The Roman demigod camp will not be kind to him if he can’t keep up with them.