The Caribbean Mystery is a remake of Mr. Moto on Danger Island (1939)-which in turn was a remake of Murder in Trinidad. James Dunn stars as Mr. Smith, a Columbo-like Brooklyn detective who pops up on a tropical island to track down some missing geologists.

The new boarder at a Washington, D.C. rooming house for women likes the fast life, but her recreational activities lead to her involvement in murder.