In the first part, Merry is used in an anti-terrorist operation that includes snakes chasing her, but does not remember it when she wakes up in a padded cell under ARC. Dr. Otto, Kam, Kerry, and Chris are in charge of her, as the CIA handed her over to them as insane. Given the four-way conversations in her head, they seem to be correct. They have her talk to some psychiatrists. The only one who is helpful is Chris, who talks to the personality Chaddy, who is Chad as a young boy. The other personalities are introduced as Chad, Merry, and Mai, who is partly Merry and partly the Palm AI who got into her head. Dr. Lenston tries to frighten Merry into submission by bringing up her phobia of snakes, and she tries to kill him.
In the second part, Mrs. Potter talks to Dr. Otto and suggests that he should introduce Sara to Merry. Sara talks to each personality in turn. When Sara talks to Chaddy, she helps them deal with John’s death. Chad gets a crush on her and tells her about the supposed insulin implant that he thinks is something else. Sara offers Merry her mark, in return for her help in putting her life back together, and Merry accepts, with the others’ consent. Mai offers Sara absolution. Dr. Otto offers to let Merry read Dr. Palm’s notes.
In a parallel story, Insanity Prerequisite - Part 3, Sara disagrees with Dr. Lenston's treatment strategy and chases him from the area.
In the third part, Dr. Otto talks to a doctor from NEXT, finds out about the hypnosis they used on Merry, and removes it. Merry starts looking at Dr. Palm’s notes, and has odd reactions to the magical sections. The doctors scan her implant, and discover that it includes a bomb. Dr. Otto calls in Dr. Tanaka, who also finds the experimental drug that was in the implant. When Sara comes to visit, she realizes that Merry’s reactions to the notes were because she was inducted as a Knight of the Church.
In the fourth part, Dr. Tanaka performs the surgery to get the implant and bomb out of Merry. Sara goes out to catch some food and ends up sleeping with Carl, an out of control werewolf. By their laws, he raped her, technically, so he now has to marry her or be neutered, which Sara doesn’t want. Merry’s operation is successful, but she has an odd reaction to the medicines, and when Dr. Otto goes to check on her, he ends up in a Loony Tunes dream for a while. Tammy and Bill come to visit Merry, and bring her the ring she got from Father Pete. When Merry puts it on, she meets Arturo and is put through a trial by fire to become a full Knight.
In the fifth part, some of the Knights of the Church discuss their newest knight, and Arturo heads to ARC to see her. Sara starts teaching Merry to shield. Sara also brings in a micro-computer and rides with Merry into cyberspace, where they both face some of their traumatic memories. Merry recalls seeing her brother killed, while Sara remembers having inducted some childhood friends into a make-believe cult of Kellith that became real. Sara and Merry discuss the possibility that her fear of snakes may have been implanted.