When Bailey is trapped putting her life in danger, Nolan discovers that Rosalind Dryer has returned. The LAPD and FBI must join forces and learns the killer's endgame before its too late.
- The Apprentice: We're introduced to another of Rosalind's acolytes, Jeffrey Boyle, who's method of killing involves trapping his victims in large tanks rigged with various booby traps and obstacles designed to torment his victims while preventing them from escaping or being rescued.
- Boom, Headshot!: How Rosalind meets her end.
- Crazy-Prepared: Rosalind's new apprentice is this in the design of his death traps with booby traps built-in to prevent the police from easily getting to Bailey that can either be activated remotely or automatic.
- Death Trap: Rosalind's apprentice uses these as method of killing his victims, building elaborate cages with built-in security measures used to prevent both those trapped inside and those who try to help them from escaping.
- Killed Off for Real: Rosalind Dyer.
- Sadistic Choice: Rosalind's final stage of the plan is to have Nolan makes one of these: either he kills Rosalind to save Bailey, sacrificing his morals and possibly goes down for murder, or he spares the Serial Killer but loses Bailey in the process. Nolan ultimately chooses the former, but the others are able to save Bailey in time.
- Stalker with a Crush: Rosalind's actions come off as this despite sex or romance never being a part of MO or profile. She has Nolan's girlfriend kidnapped by her acolyte Jeffrey Boyle in order to draw him to her, where she and John dressed in fancy dress and have dinner. The end-goal of her plan was to either have him murder her to spare Bailey or spare Rosalind and let Bailey die.
