Deputy Marshal Sam McCloud of the small western town of Taos, New Mexico is assigned to the metropolitan New York City Police Department (NYPD) as a special investigator.
The head of a trucking company is killed before eyewitnesses, and McCloud's girlfriend is the culprit.
On Christmas Eve, an assassin stalks McCloud, a spurned mistress attempts suicide, a sidewalk Santa turns mugger, junkies raid a hospital pharmacy, Chris's newspaper organizes a party for orphans at Westside Hospital with Chief Clifford as Santa, and the junkies take hostages.
McCloud is framed for the murder of a drug-dealing hack, and exposes the ring.
The State Department sends Chief Clifford and McCloud to Moscow with a touring country & western singer, undercover.
A peer of the realm, who's a photographer as well as a cat burglar, comes to America and, in flagrante delicto at a Long Island costume party, witnesses a killing at the hands of Irish bombers, all of which sends McCloud to Blighty, where the target remains to be found.
Murder victims are found to be drained of blood, and an elderly star of vampire films is suspected; Chief Clifford is on the hunt for a random sniper.