Unknown to everyone but his shady Middle Eastern bosses, watchmaker Hawkins is actually a professional hired assassin with a predilection for killing his targets with bombs. After disposing of a dictator and millionaire, Hawkins is assigned to kill a politician who is heading to a remote hotel, The Green Man, for a secret tryst with his secretary. There, however, Hawkins' plot is discovered by vacuum salesman William Blake, who determines to stop him.
A race car driver marries a woman for her money and plans to murder her. An old suitor steps in to help her but the driver takes steps to eliminate the rival. But there's a flaw in the driver's plans.
P.C. George Dixon is a long-serving traditional copper who is due to retire shortly. He takes a new recruit under his aegis and introduces him to the easy-going night beat. Dixon is a classic ordinary hero but also anachronistic, unprepared and unable to answer the violence of the 1950s.