After trying to smuggle a package into prison for his father Willi, Harry and his girlfriend Marlies also end up in jail. While Harry is billeted with Daddy, Marlies is housed just one floor up in the cell of the ageing prostitute Jutta. With Christmas just around the corner, the four of them join forces and plan to break through to their cells to celebrate a lavish party with a can of homemade schnapps.

Marty Mackenzie is an unsuccessful stage actor who takes an interest in private investigating. He takes a job working with Jack Potter, a crusty private eye. They both take a case in Beaver Ridge, a seedy small town where a murder is being planned against a rich gravel pit owner. Marty realizes that private investigating is not as it seemed to be.