The Mystery of Marie Roget is a 1942 mystery film starring Patric Knowles. The story was adapted from the short story "The Mystery of Marie Rogêt" written by Edgar Allan Poe in 1842. The film, directed by Phil Rosen and produced by Universal Pictures, is set in 1889.

Plot
In 1889 Paris, musical comedy star Marie Roget has been missing for ten days. Police inspector Gobelin is investigating her disappearance. The French Minister for Naval Affairs, Henri Beauvais, a friend of Marie's grandmother, Madame Cecile Roget, and her younger sister Camille, threatens to take Gobelin off the case. Therefore, Gobelin brings medical officer Dr. Paul Dupin into the case.

The body of a dead woman is found in the river. Although her face is mutilated, Beauvais believes it is Marie. But then Marie returns, but refuses to say where she has been. Camille becomes engaged to Marcel Vigneauz. Marcel and Marie are lovers and planning to murder Camille, who is set to inherit a fortune. Cecile Roget asks Dupin to escort Camille to a party as she fears her granddaughter shall be murdered there. At the party, Beauvais propositions Marie, telling her that he knows of her affair with Marcel. Marcel hesitates to kill Camille, causing an argument between him and Marie.

Marie disappears. The body of another faceless woman is found. Dupin sneaks into the morgue to remove the brain from the second woman's body, and identifies it as Marie. Cecile tells Camille about Marie's plan to kill her. Marcel confesses to killing Marie, but says he did so to save Camille. Beauvais demands the charges against Marcel be dropped and Dupin agrees. Marcel challenges Dupin to a duel. Gobelin learns from Scotland Yard that the first dead body was that of Marcel's English wife, who had recently come to Paris to find her husband.

Dupin and Gobelin discover Beauvais and Marcel have gone missing. Dupin reveals he accused Camille of having Marie's diary, even though he knew the diary didn't exist, so the murderer would retrieve it. They arrive at the Roget home just as Marcel was going to kill Camille. Gobelin shoots Marcel. Gobelin afterwards discovers that Beauvais has been secretly helping Dupin.