"The Unknown" was the final entry in Columbia’s I Love A Mystery series. A woman hires two detectives to keep her alive long enough to claim her inheritance.

A man listens to his wife and fakes his own death so that she can get her hands on his insurance policy.

Fred J. Johnson scores a hole-in-one but his next drive, using the lucky, initialed golf ball, soars out of bounds and lands near a spot where some counterfeiters are burying a murder victim. Then begins a series of events in which he is hounded and threatened by the killers. The consequences of his not reporting what he saw to the police lead to a climax in which is daughter is held hostage by the crooks.

A private eye and her sidekick solve the case of a dead client.

A criminal psychiatrist investigates the murder of a two-time widower.

Panic arises among Allied POWs aboard a Japanese freighter when they learn that the ship is actually a decoy target for American submarines on night patrol. The prisoners unite and attack their Japanese captors just as an American sub surfaces and, not knowing the prisoners are aboard, prepares to torpedo the ship.

Ex-thief Lone Wolf and his valet don turbans to solve a museum jewel theft.