When a series of murders in the run up to Christmas are found to be linked, FBI Special Agent Natalie Parker is tasked with tracking a pair of psychotic serial killers that have based their personas on Santa and Mrs Claus. As Christmas approaches, they slaughter their way through their naughty list, playing a cat and mouse game with the FBI and leaving a trail of bloody bodies in their wake.

When a woman is murdered, and her fiancé is the prime suspect, successful matchmaker Angie works to prove her client's innocence, much to the dismay of Kyle, the detective working the case.