The London police hire McGill to bodyguard a stool pigeon who is ratting out his brothers on a murder charge. Problem is, the pigeon doesn't want to cooperate and his brothers' boss wants him dead.

McGill's friend, a Russian defector, has absconded with a million dollars and hidden the safety-deposit box key. Some people will kill to get it, and when one of them succeeds, McGill finds himself caught in the middle.