Bulldog Drummond finds himself immersed in another adventure when he stumbles upon a corpse in the mysterious London mansion of Prince Achmed. Enlisting the help of his old friend Algy and the beautiful Lola, Drummond uncovers a scheme to ship illegal cargo into the country. He must rely on his cunning to survive when the prince offers a reward for his capture.

A tramp gets drunk in a hotel lobby and, upstairs, causes some misunderstandings between Mabel, two hotel guests across the hall from her room, and Mabel's visiting sweetheart.