The Fire Inside

S2, E16: When victims are burned to death by a psychotic killer called "The Dragon," Nick Knight races against time to protect a band of homeless living beneath the city's streets. The investigation into the gruesome murders is even more difficult for Natalie and Captain Cohen as the "crimes of fire" rekindle Natalie's childhood memories of a fiery car crash and Cohen must deal with her disturbing memories of the loss of her first partner to "friendly fire" during a drug raid.