Best Mystery Movies of 1938

While Charlie is distracted with the birth of his first grandchild, son Jimmy impersonates his father in order to investigate a murder aboard a freighter in the harbor.

Pepe Le Moko is a notorious thief, who escaped from France. Since his escape, Moko became a resident and leader of the immense Casbah of Algiers. French officials arrive insisting on Pepe's capture are met with unfazed local detectives, led by Inspector Slimane, who are biding their time. Meanwhile, Pepe meets the beautiful Gaby , which arouses the jealousy of Ines

When the murdered body discovered by beautiful, vivacious socialite Melsa Manton disappears, police and press label her a prankster until she proves them wrong.

Nancy Drew and Ted Nickerson solve a kidnapping case of a wealthy elderly lady. Ted has to disguise himself as a nurse while Nancy becomes a "widow" in order to locate the lady they are rescuing.

An investigator for the District Attorney's office quits to open his own detective agency. However, business is so bad that he finally decides to give it up and go back to his old job. As his wife is at his office closing up, a wealthy society matron walks in with a case: she wants to know if her husband is having an affair with his ex-girlfriend, who is now married. The wife accepts what looks to be an easy case, figuring than she can then persuade her husband to re-start the agency. However, when the client's husband is found murdered, she decides to investigate the murder herself. Her husband has also been assigned by the D.A. to investigate the murder, and he doesn't know that his wife is also on the case. Complications ensue.

The invention of a machine that can cause remote explosions brings the attention of Scotland Yard and Bulldog Drummond.

This murder mystery is set behind-the-scenes of a radio station. the trouble begins when a hated cad of a sponsor is found murdered during the climax of a live radio show.

A notorious counterfeiter passes himself off as a Secret Service agent to Steve and gets him to unwittingly help him bilk the racetrack out of tens of thousands.

A religious fanatic finds his entire life and philosophy turned upside-down as he falls in love with a girl and kills her in a jealous rage. His search is for peace of mind and a desire to justify the murder of the girl to himself. His mind becomes distraught as he gropes trying to rationalize his deed and his world falls apart around him. A police inspector patiently and tirelessly stays on Barrault's trail, without putting him under arrest, though convinced he is the murderer, and waiting for the moment when he feels Barrault will break under the strain of his own religious fanaticism (IMDb).