Former CIA operative Dr. Dylan Reinhart (Alan Cumming) is lured back to his old life when NYPD detective Lizzie Needham (Bojana Novakovic) 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 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.