Two passerby discover a severed head in a pond near a park. Dylan and Lizzie investigate and find there are three additional severed heads in the pond, but no sign of the bodies. The coroner finds that the heads were ...
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.
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 have trouble identifying a motive or connection when several average people blow themselves up using suicide bombs; Julian is concerned that Dylan could be exposing himself to past enemies.