Max and her family (Fang, Iggy, Nudge, Gasman, and Angel) are only 98% human. They grew up in The School (a science lab they consider a prison) which was guarded by vicious Erasers (part human, part wolf men that can transform into beastly creatures).
Max is running through the woods being chased by Erasers when she comes to a cliff. She lets herself fall off and down before opening her wings. She flies into the sun to prevent the Erasers from shooting her out of the sky. Max wakes up from the dream.
Max (the oldest) and her family of bird kids live alone in a house on a cliff. Jeb Batchelder had taken care of them at first, but he disappeared and they assume that he is dead. Max has taken over the responsibility of watching over the other five bird kids. Gasman (8) has digestive problems and is actually blood related to Angel. Iggy (14) is tall and blind, but a better cook then the others. Fang (14) is just a few months younger than Max and is very quiet. Nudge (11) likes to talk all the time. Angel (6) is Max’s favorite. She is also a mind reader that likes enclosed spaces.
The kids go to pick wild strawberries. Gazzy uses his ability to sound like anyone to mock Max’s cooking. They are ambushed by Erasers and are outnumbered and overtaken. The bird kids are stronger than the average human, but the Erasers strength is greater than theirs. Ari (Jeb’s seven year old son) is one of the Erasers. He recognizes Max, but it takes her a minute to realize who he is. The Erasers take Angel and leave the rest. The flock agrees to go after her. Iggy hears an engine and they fly after it. Fang smashes the windshield with a tree branch, but then the passengers pull out guns. Max tries to get Angel back when the Erasers switch from car to helicopter. She ends up hanging on to the landing skid as they take off, but is unable to hold on when Ari points a rifle at her, saying that his group is the good guys.
The rest of the flock returns home and start bickering with one another in frustration. They start brainstorming about where Angel is being taken, but the answer is obvious: The School. This is the place that doesn’t want the flock seen because it would expose the horrible genetic experiments they are doing on children. Iggy is currently blind because they tried to improve his night vision. The flock starts going through the papers that Jeb left behind. In a sealed envelope are plans and maps of The School.
Iggy expresses his concerns about going after Angel (guns, helicopters, etc.). Max tells him he doesn’t get a choice in the matter: Iggy and Gazzy are staying home. Iggy’s blindness is too much of a liability in unfamiliar territory. Max is unsure whether The School also wants Angel’s brother, Gazzy, as much as her.
Max, Fang, and Nudge start flying to Death Valley, California to rescue Angel. Nudge tells Max that she found Jeb’s file with her real name (Monique) on it, and the file gave some names and a city called Tipisco, Arizona (right on the California border). Max denies Nudge the idea of meeting her real parents until Angel is rescued.
Angel is in a cage and tries to communicate with the two boy experiments in the cage next to hers. A couple of whitecoats come in, excited to see her, Subject 11. One cannot wait to section Angel’s brain. The two boys are relieved it is not them that they whitecoats came for.
Max, Fang, and Nudge break into an empty ski cottage and find canned food. They sit and eat and decide to rest for a little while.
Iggy and Gazzy are frustrated that they were left behind. They start making plans to protect the house in case the Erasers decide to come back for them.
The whitecoat, Reilly, made Angel run for three and a half hours, shocking her with a stick if she tried to stop. She eventually collapses and the whitecoats converse about cutting up her brain.
Max realizes that they overslept and gets Nudge ready to go while Fang packs cans of food in a backpack. Fang uses logic to calm Max’s guilt about oversleeping. Fang and Nudge ask about how they will rescue Angel. Max doesn’t tell them that if nothing works, she will trade herself for Angel. While they are flying, Max sees a bunch of boys bullying a girl and decides to go help her. She sends Fang and Nudge ahead.
Iggy and Gazzy start making a bomb. They decide to use Max’s Mickey Mouse alarm clock for parts as revenge.
Max saves Ella from the three boys. She accidently beats them up a little too much, not realizing at first how fragile humans are. One pulls out a shotgun and Max runs through the woods. However, she is shot. She falls down a ravine and finds that her wing was hit. She succumbed to her fatal flaw (fighting for the underdog) and now felt like she was letting her flock down.
Fang and Nudge fly to a high up cave above Lake Mead to wait for Max. Nudge steps out on the ledge and sees Ferruginous Hawks. The two bird kids sit quietly and allow the birds to get used to them so that they do not attack. They watch the birds and try to imitate their moves in the air. Nudge starts to worry about Max and Angel.
Max wanders through the woods avoiding the humans. She eventually comes to a house and Ella is letting her dog out. Max asks Ella for help and then has an internal debate on whether to stay or run away. Ella sees the blood and gets her mom, Dr. Martinez. Ella’s mom comes and brings her veterinary equipment. Max has no choice but to show her shoulder as well as her wing. The two humans are surprised by what they see, but are still willing to help Max.
Angel wonders where Max is. She had bitten Reilly earlier and he hit her in the face. One whitecoat advises the other to be careful with Angel before he takes blood from the shunt in her hand. Next, she is forced to run through Mazes that shock/burn her when she slows down. Eventually, she reads the mind of the one building the mazes and goes through it quickly. Jeb comes to greet her.
Iggy and Gazzy have finished their time bomb and are setting traps. Two Erasers in a Hummer hit a tarp covered in oil and flip the car. Thy walk away from the accident and Gazzy describes the scene to Iggy. They go to an abandoned logging house the flock has used as a clubhouse in the past. Two Erasers show up, blocking the exits. Iggy and Gazzy narrowly escape through the roof. Iggy drops their home made bomb, killing the two Erasers. The two in the Hummer are searching for them with binoculars, So Iggy and Gazzy fly away. After hiding for a while, they decide to go find the rest of their flock.
Fang and Nudge start looking around for Max, not wanting to get too close to where they left her. Nudge sees a sign for Tipisco, Arizona and decides to find her parents. Fang tries to tell her not to, but Nudge refuses to listen. She finds the address she remembered from her file. A woman walks out of a trailer with curlers and lights a cigarette. Nudge is about to approach her when Ari and two other Erasers appear behind her and Fang. Ari tells them that the rest of the flock has already been killed. The two bird kids use what they can find to fight off the Erasers and get away.
Max is left alone with Dr. Martinez when Ella goes to school. She tells the doctor a few things about her, but tries to keep her origin and her flock a secret. Dr. Martinez takes Max to her office or x-rays, using the excuse that she is a student writing a paper. Max has muscle tissue damage, but it is healing at a faster rate than normal humans. The x-ray also shows a tracking chip in her arm. Dr. Martinez doesn’t think that she can get the chip out because it was implanted when Max was so much smaller. Two Erasers come in looking for Max, who Dr. Martinez has hidden in a closet. The doctor chases them away. Max agrees to stay the humans one more night.
Jeb tries to win Angel over with food, but she doesn’t trust him. She is also wondering why she can’t hear his thoughts at all.
Max makes chocolate chip cookies with Ella and Dr. Martinez. She later tells Ella that she has to leave the next day and probably won’t be able to visit, which makes Ella sad. Max likes having a sense of normalcy with these regular humans. The next day, she takes off, hoping Fang and Nudge are still waiting for her.
Fang steals some kabobs from some nearby campers and brings them back to Nudge. The start eating and Iggy and Gazzy show up, explaining how the mountain they used to live on is covered in Erasers.
Max is still a little sore, but is able to get to the other four bird kids. Everyone explains what happened while they were separated, and they take off to go save Angel. Knowing they need to refuel and can’t fly all the way to The School, the flock stops and hides in some bushes near a shopping plaza. An angry man yelling at someone over the phone stops at the ATM to take out money. Ari and other Erasers show up and scare the man away. They chase after him in their own car, giving the flock an opportunity to steal the man’s forgotten ATM card. Iggy listened while the man punched in the PIN and is able to figure it out. Max is reluctant about “borrowing” a van from some kid that just went to work until they hear a helicopter in the distance.
After wondering around trying to use her internal sense of direction to find the school, they decide to go to a small town called Bennett or food and a map. The flock goes into a fast food restaurant and order mounds of food. They start eating, but don’t realize that the crowd around them have been replaced by Erasers. They get back into the van and Max drives them out of town. She tries to cut through a cornfield to loose the Erasers that are chasing the, but ends up crashing the car on the other side. Everyone seems okay, but the Erasers quickly come after them. Ari is surprised that the flock does not seem to want to return to The School.
Max, Fang, and Nudge are captured and put into cages in the same room as Angel. Jeb shows up to greet Max, saying he has missed her. He takes Max into a private room to talk to her. He says that her purpose is to save the world. Max continues to stay silent and is eventually returned to her cage. The whitecoats and Erasers, including Ari, load the cages onto a cart and wheel them outside to the yard where Erasers are trained to hunt their prey.
Ari taunts Max and pokes his finger in her cage. She bites down until he throws her cage near Angel’s. She unlatches the other cage and tells Angel to get away. Iggy and Gazzy are leading the hawks to The School as reinforcements. Max fights some more and is able to free Fang and then Nudge. The flock is ready to fly off together with the hawks. The bird kids realize that they need a new home. Max feels like going to the east coast will be a nice change.
The flock starts heading east. Max gets a blinding pain behind her eyes and can’t do anything, including staying air born. Fang catches Max and carries her to the ground. When the pain subsides, they start cooking whatever they can find over a fire. Max is worried that she is nearing the end of her life-span. Angel has a secret to tell Max that she learned while at The School: their prison is run by a larger place called the Institute. Also, they have real parents. The bird DNA was added while they were still in the womb. Nudge and Fang’s parents were told that they died. Iggy’s mom died giving birth. Gazzy and Angel’s parents sold them to the school. However, Angel didn’t learn anything about Max’s parents. Everyone tries to deal with this news.
The kids take off, but the pain in Max’s head returns and she falls to the ground. They take off again, this time Max is able to stay up. Nudge wonders out loud whether her parents would want her. Max is reminded of Dr. Martinez and Ella.
There is a Taylor Twins concert in Central Park, so the flock lands there and hides in the crowd. Afterwards, they fly up into a tree for the night. Nudge loves the excitement of New York, but Iggy finds it harder to navigate with so much noise. The next morning, they wake up to find the park is busy. They start about their day by getting food, but quickly start being followed by more and more Erasers. They make their way into the zoo (which is having a school day). The younger kids enjoy the experience, but the older ones start having trouble with claustrophobia. They leave and wonder around the city for a while.
Fang suggests that they look for the Institute in the phone book. Max notices that they are in front of a library and they all go inside to do some research, but have no luck. The flock decides to leave and take the subway back to Central Park to sleep again. When no trains arrive, they start to worry. Iggy hears voices approaching and they start running down the tracks until they find a city of homeless people. They decide to stay there for the night, sleeping on a ledge.
Max wakes up in pain, just wanting it to end already. A boy comes up to her and accuses her of messing up his mother board. He shows her his screen and she sees the images that have been flashing inside her head. The kid gets freaked out when the computer welcomes Max to New York. A voice in her head says that she new Max would come. The pain increases and the screen changes to say, “The Institute of Higher Living.” Fang also saw all of this happen. They start asking the boy some questions, but he gets paranoid and leaves.
The flock sets out on the streets again in the morning. The voice in Max’s head tells her to get on a bus and take the stop that sounds fun. They listen and end up at a large toy store. Angel asks for a $49 stuffed bear dressed as an angel. Max refuses, so Angel gets inside a lady’s head and has the lady by it for her. Max is disappointed in Angel’s actions.
The voice is still trying to convince Max to relax when Erasers show up. The flock starts running, but one grabs Max. She is unable to fight it off, but it soon drops down dead. The rest of the flock comes to Max. They see from the tattoo on the dead Eraser’s neck that he was only five years old. Nearby, Max finds an ATM card with her name on it. The voice tells her that she can use it if she can figure out the password.
They return to Central Park and start sleeping in a tree. The police come along and tell them that they are not allowed to do that. They end up running away from the police and hiding in St. Patrick’s Cathedral. They decide that this is a safe place to spend the night.
The pain returns and Max sees a greenish building on 31st street. The flock decides that they should find the building. Along the way, they try the ATM card. Eventually, Angel comes up with the password: mother. They find the building, but not the Institute. The receptionist’s computer screen tells them there is a pot of gold beneath every rainbow. Max asks if the building has a basement. The security guard chases them out.
Gazzy breaks down in frustration (which is unusual for him). Max agrees to go sit, eat, and rest somewhere to help cheer him (and everyone else) up. They go into a fancy restaurant that excites the younger kids and makes the older ones anxious. The waiter takes their order, but is shocked by how much they asked for. The manager comes over to try to get them to lessen their orders. Max refuses and they are asked to leave. Before they can, the police show up from the front and kitchen. They decide to fly out the sky light.
Back in a tree, the flock discusses the situation and how pictures were taken of them flying. Ari and some other Erasers show up and surround the tree. Angel accidently drops her bear, Celeste, and Angel jumps down, concentrates on making Ari drop it, grabs it, and gets back in the tree. The Erasers are called back by the director.
The flock finds a new shelter on top of a building that is in being constructed. Max starts to worry about Angel using her power to get her way all the time. The fall asleep and when Max wakes up Fang gives her breakfast and some newspapers with their picture on the front page. They decide to lie low for a while.
They head into the city for food and are offered free makeovers. Max accepts because she thinks this will help them be unrecognizable from the pictures. They also go to a second hand store for new clothes. That night, they take flight to leave the city. They go to a vacant beach and find huge rocks that make a decent shelter. The flock seems to love the beach. Fang asks Max if she would forget the mission and stay there if she knew they’d all be safe. She starts wondering about sides in the game, whether or not one of them is a double agent. She wonders if Angel is different since they got her back. Gazzy is worried because Angel hasn’t surfaced from the ocean water in a while. When she finally surfaces, they find out that she has tiny gills that allow her to breath under water.
The next day, Max is woken up by Ari. Angel, Gazzy, and Nudge make it into the air. Fang knocks Ari off Max and takes a beating. They are surrounded by hundreds of Erasers. Jeb stops Ari. Max tells Jeb that she want out of the game. He says she is the greatest and must save the world.
Max checks on Fang. He wakes up and she kisses him, sure that she is loosing her mind. Fang declares that he is going to kill Ari.
Back in the subway tunnels of New York City, Max scares away the hacker boy the met before by telling him about the chip that is implanted in her arm. That night, Max dreams about where the Institute is. The flock follows the dream through the sewer system. Max’s vision suddenly has a built in map, which seems to be temporary, and follows lights that only she can see. When they come to a door, Iggy picks the lock. They open the door and start down the stairs. They eventually end up in a lab that looks just like the one at The School. Nudge touches the computer Max is at and finds the password (she can see what people have previously done with an object). Max finds their origin documents and prints them. Fang rounds up the gang, but Gazzy is distracted by another lab with caged subjects in them. They set the creatures free and get as far as the sewer before Ari shows up.
Ari explains that the scientists start the Eraser process on him when Jeb left with the flock. Ari claims that since they waited longer before starting the mutations, he is a super-Eraser. Max tells Fang to get the others out while she fights Ari. She finds an opportunity and takes it, possibly breaking Ari’s neck. He says that he never would have hurt her like that. Max and Fang fly through the tunnels and they hear Jeb yell in anguish. Max yells back that it was his game that did this. Jeb replies that she killed her own brother.
Fang informs Max that the other mutants left, not wanting to stay with the flock Angel adopts a dog, Total. They agree that she can keep him as long as she takes care of him. They start going through the pages Max printed off. Everyone seems to find info about their parents except Max. She tells them that they will go look for them. The voice in Max’s head says that it is a friend.
The flock starts out to find their parents. The voice interrupts, saying that Max needs to focus on the world, not just her flock. Max replies that the flock is her world.