Gaston, a veteran of World War I suffers from amnesia and has spent the last 18 years in a hospital trying to regain his memories. Although he is claimed as a son by various families, a rich Duchess believes the true family Gaston belongs to is the Renauds. Gaston travels to the Renaud's estate alongside his lawyer Huspar. A docile character, Gaston discovers his former identity of Jacques Renaud: a cruel and violent young man who used to kill animals for sport. He learns that immediately prior to the war he pushed his best friend, Marcel, down a flight of stairs, breaking his back, shortly after witnessing him kissing the maid Juliette, with whom Jacques had been intimate. He has difficulty reconciling his current personality with that of his past. His brother's wife, Valentine, (with whom he had an affair during adolescence), proves that he must be Jacques Renaud by telling him about a scar he has. Jacques had a tiny scar on his shoulder from where Valentine attacked him with a hat pin in a fit of jealousy. Gaston then sees this scar in the mirror, but does not tell Valentine about it. Soon thereafter, numerous families arrive at the Renaud estate searching for their lost loved one from the war. Gaston spots a young boy. This boy, who is the only surviving member of the Madensales, a family who died in a boating accident when he was an infant, is searching for his long lost nephew who happens to be much older than himself. Gaston tells the young boy about his scar on his shoulder and fabricates a story about the scar belonging to the boy's long lost nephew. Gaston leaves the Renauds to become a member of this boy's family, later writing a letter to Jacques's brother Georges stating that their Jacques is dead and they need not search for him any longer.