Plot

Dr. Russell, a specialist on diseases of the brain, is traveling with his young wife and stays for a few days at a fashionable hotel where the guests are given to merriment. There the wife meets one Marius, a polished man of the world, who is immediately smitten with the charms of the wife. She is not averse to a flirtation and at a ball they meet in a clandestine manner and Marius wins the woman. Dr. Russell is summoned home, but his wife finds an opportunity to communicate with Marius and invites him to call on her in a secret manner. Dr. Russell returns to his home, which is a private sanitarium for the treatment of the insane. His wife has arranged with Marius to effect an entrance into the home by waving a lamp as a signal that the coast is clear. Marius arrives during the absence of the physician, sees the prearranged signal and enters the house, which is in darkness. He is groping about trying to find the woman when the husband unexpectedly returns home with a madman. Fearful of being discovered, Marius seeks concealment in a cell, which is numbered 13. The wife is unaware of his presence in the house. Dr. Russell and his assistants place the lunatic in the same cell. Marius tries to make his escape, but finds the door locked. The insane man is awakened and he grapples with the intruder and a fierce fight ensues, in which Marius is borne to the floor and throttled. The noise of the struggle reaches Dr. Russell's ears and he goes, with a helper, and rescues Marius. The latter has been made insane from fright and he partially recognizes the wife and hands her the letter she has written him. The physician obtains the letter and learns of the infidelity of his wife.—Moving Picture World synopsis