In the last book, the Sons of Ramero set up an elaborate prank, Karen Desonne is shot down by a police officer and later let go by the same officer. Passing Strange starts off from Karen's point of view after she is already home for some time. She has found that her gunshot wound to the face is healing, but still cannot return to school because zombies have been banned. All of her undead friends, besides Adam, have decided to hide in the lake that has frozen over. However, since Karen is still "passing" and no one there knows that she's undead, she decides to return to work at the mall. She has cleverly disguised herself with zombie makeup and blue contact lenses. While working one day, she meets zombie-hating Pete Martinsburg and decides that she is going to learn what is going on through him. She flirts with him and he shows interest, not recognizing her from his previous attempt to kill her. Karen decides that she may be able to use this situation to her advantage.
Peter Martinsburg has been recruited by a church to help them take down the zombies. He has been helping Duke set up the zombies for various crimes, including murder. After meeting Karen (who is using a fake name) at the mall, he is shipped across the country to a Christian camp shortly after. He spends some time with others the Church of Light have recruited for their mission against zombies. Eventually, he is sent back home to help find where the zombies have hidden.
Upon Pete's return, he starts dating Karen. She decides that she is going to find out what his plans are. Eventually he reveals to her that he intends to kill her friend, the zombie-loving Phoebe. He has been watching her to determine how to do it. She makes sure to put herself into the plan so that she can prevent this from happening. She goes into the frozen lake to tell Tak was is going on and asks him to watch over Phoebe. He complies and takes Popeye and another zombie with him for the task.
On the night of the attack, Karen is driving Pete's car. Pete, wearing a mask that makes him look like Tak, goes out back while Phoebe is letting the dog out and starts to approach her. Tak and his group start coming out of the woods to save Phoebe, but she is confused by his sudden appearance. Before Pete can do anything, Karen honks the car horn, indicating that something isn't right. Pete runs back to the care where Karen explains that she got scared. Pete comforts her and realizes that it was not a good plan anyway.
Pete spends some time with Duke at the Center and Duke reveals to Pete that Karen is a zombie. To take his revenge, Pete goes to the mall while Karen is working. Karen realizes that he's acting strange, but can't figure out why until Pete points out that he has been sticking pins in her without her realizing it. Everyone realized that she was a zombie and she was arrested. Before they cart her away, she is able to stick a knife down her throat.
At the prison, the cop that originally shot her comes to apologize. She then decides that she is going to get out of there no matter what. She uses the knife to cut herself up until she appears to be dead. In the process of the ambulance taking her to the Center for research, Tak and the boys rescue her. They all end up going to the center with Phoebe and Adam.
When they leave the Center, Karen reveals to Tak that she is gay and going to go see her old flame. He is disappointed that she cannot return his affections, but understands.
Kiss of Life