Fraser's next task is to escort a Canadian Diplomat's daughter to a ball, meanwhile, Ray is trying to track down a murdered mobster's contact list. Little do they know, their tasks will soon merge.

While in pursuit of fleeing diamond thieves, Fraser is thrown from the back of the van and is so badly concussed that he loses his memory. With no other witnesses and the hostage in jeopardy, Ray must race to help get Fraser his memory back and recall the van's licence plate number, by seeing if anything familiar speeds up his recovery.

Fraser and Kowalski begin a murder investigation that leads them on a Great Lakes freighter.

Ray's bust of an illegal poker game is interrupted by a gunman who makes off with the money. The Chicago PD arrest the players, one of whom becomes bait in an even higher stakes game.