James Raven is a sociopath and a killer, born disfigured with a harelip. He is also cold and without remorse. His father was hanged, his mother committed suicide, and so he was institutionalized. Now a professional assassin, his assignment is to kill the minister of war bringing about a chain reaction of countries preparing for armed conflict. Other than having to kill the minister's secretary, the hit goes fairly smoothly until he learns he was set up by the people who hired him.
Raven is given marked bills that are traced directly to him. He is almost turned in by an unscrupulous doctor from whom he wished to have his harelip operated on without anesthesia. Fleeing London in pursuit of a man named Cholmondeley (pronounced Chumley), he boards a train and encounters a woman named Anne. Disembarking in Nottwich, she is taken prisoner and learns the circumstances of his crime and set up. Raven takes her to an empty home up for sale, until a sales agent and prospective buyer come in, forcing Anne to use her wits to escape from him. By chance she encounters Cholmondeley, now calling himself Willy Davis at the theatre where she works. Thinking he is harmless, she is taken to dinner as she is trying to learn more about him and his part in the effort to start the war. When she becomes too inquisitive he kidnaps her.
Anne's fiancée Mather, an investigator for Scotland Yard, learns she is mixed up in the situation. Raven spots Anne's purse being carried by an old woman and pursues her home to the brothel where Anne was abducted the night before. Mather and his partner Saunders have been keeping Raven under surveillance and follow at a distance. Raven finds Anne, tied and gagged in a pantry and they leave for his hideout in a work yard as night closes in. Sir Marcus, a principal with Midland Steel would benefit handsomely from the outbreak of war, is the mastermind pulling all the strings. He employs Davis and wants Raven killed immediately, telling Major Calkin to call the police with that directive. Calkin refuses as the work yard is surrounded, Raven will be caught in the morning. Dawn breaks as a fog has settled in and Anne allows Raven to escape the police dragnet; he heads to Midland Steel to look for Davis.
An air raid drill is underway on Christmas morning in Nottwich and all citizens are required to wear gas masks. As medical student Buddy Ferguson is taking advantage of the situation to torment a school rival he has the misfortune to cross paths with Raven. Raven ties him up after taking his clothing and gas mask. Now Raven is perfectly disguised to exact his revenge upon Sir Marcus and Davis who have double-crossed him. Anne tells Mather the unbelievable tale and they await Raven's attempt to get at Sir Marcus at Midland Steel.
This report prepared by David Fletcher