When a psychopath commits murders based on novelist Castle's books, Detective Beckett seeks his help to solve the case. He decides to work with her and uses his experiences as research for his novels.
F.B.I. Special Agent Seeley Booth teams up with the Jeffersonian's top anthropologist, Dr. Temperance Brennan, to investigate cases where all that's left of the victims are their bones.
In the 1890s, William Murdoch uses radical forensic techniques for the time, including fingerprinting and trace evidence, to solve some of the city's most gruesome murders.