The mysterious and grisly murders of a mother and daughter leave police investigators puzzled. Few clues were left behind. The killer could not have fled via the windows as they were nailed shut. Nor was the killer observed leaving by neighbors. It seems the only person with the skills to solve the crime is Auguste Dupin, who has been released from the police department by the new prefect. After much persuasion from his daughter, whose fiance is charged with the crime, Dupin begins to investigate the case on his own, and puts together quite an interesting scenario in solving the crime.