Former CIA operative Dr. Dylan Reinhart is lured back to his old life when NYPD Detective Lizzie Needham needs his help to stop a serial killer.
Although Dylan has returned to teaching, Lizzie calls upon his expertise with profiling sociopaths to assist with a bizarre case in which a venture capitalist was murdered and his body ritualistically displayed.
The murder of a young man who recently left his family's religious community leads Dylan and Lizzie to a series of possible suspects, including a short-tempered photographer and a mysterious girl with amnesia. Also, Lizzie's younger sister, Katie, unexpectedly drops by for a visit.
Dr. Dylan Reinhart and Det. Lizzie Needham are reassigned to a murder case in Central Park when their investigation into a chemical attack on the subway is taken over by an FBI team led by Dylan's estranged father, Roger. However, Dylan can't shake the feeling that the cases are related.
Dylan and Lizzie investigate the murder of a Jane Doe, but when they realize that the victim was killed by mistake, they must identify the killer's motive and intended target before she suffers the same fate.
Dylan and Julian go undercover in a hospital when they suspect an "angel of death" is killing people with non-life-threatening ailments. Also, Lizzie asks Andy for his legal expertise when a personal trainer sues her for accidentally injuring him.
Dylan and Lizzie are under pressure to deliver results when they investigate the death of Jasmine's friend, the owner of a professional basketball team who died when her car went off a bridge.
When a woman is shot outside a community center, Dylan and Lizzie are challenged by the mayor to solve the case in less than 24 hours to quell pressure from the media and special interest groups.
Dylan and Lizzie work to uncover who would want to murder an acting troupe of costumed characters when two members are killed using highly sophisticated poisons. Also, Andy encourages Dylan to accept an invitation to a BBQ being thrown by Det. Fucci when he becomes concerned that Dylan isn't fitting in with his new colleagues.
When Celia Baxter, a successful author, is almost killed in her home, Dylan and Lizzie's suspect list includes several people who may have held a grudge as she rose in stature in the publishing world. Also, Lizzie gets closer to learning the truth about the death of her fiancé, who was killed while undercover.
Dylan and Lizzie are unable to identify a motive or connection when several average people blow themselves up using suicide bombs. Julian, concerned that Dylan could be exposing himself to past enemies, enlists Lizzie to talk him out of hiring a publicist.
Dylan and Lizzie investigate the murder of a film student whose death was broadcast for the world to see. Also, Andy and Dylan realize that parenting is tougher than they thought when they agree to look after Madison, a friend's 12-year-old daughter.
Dylan and Lizzie investigate the murder of Joan's protégé, Kristy, uncovering long-buried secrets worth killing over. Also, Dylan and Andy apply to adopt a child, and Lizzie's reliance on Julian's illicitly obtained information puts a promotion in jeopardy.