A young man of society wants to make an expedition to Africa, but his fiancée asks him for help with one of her father's guests shortly before his planned departure. Her suspicions about that guest are serious: this man tries to steal one of her father's rubies, and she and her fiance' are kidnapped and taken to a house where strange things happen. The whole thing becomes a nightmare under the direction of a mysterious Mr. Satan.—Stephan Eichenberg <[email protected]>