A.A. Milne's The Fourth Wall was the source for this early British talkie. During a weekend party at the country estate of Arthur Hilton (C. Aubrey Smith), the host is impolitely murdered by his guest Carter (Robert Lorraine) and Carter's henchman Laverick (Warwick Ward). The killing is carried out with such cunning that the other guests can provide both Carter and Laverick with air-tight alibis. Just at the point when the police are about to write off Hilton's death as a suicide, romantic leads Jimmy (Frank Lawton) and Mollie (Dorothy Boyd) stumble upon the "one fatal slip" made by the two clever murderers.