Alice White, the sweetheart of London detective Frank Webber, murders in self-defense an artist who brutally attempts to seduce her in his studio. She escapes and returns home. Her distress and terror are aggravated, however, when her fiancé is assigned to the case. Frank realizes quite soon that the girl is somehow involved, and later he learns the truth when Tracy, a shady character who saw Alice come out of the studio, begins to blackmail him.