The Crooked Web (1955)

Cafe owner Stan Fabian joins Joanie Daniel and her "brother" Frank in a scheme to unearth a "fortune in stolen gold buried by Frank" in Germany during World War II, and Stan is unaware that Joanie and Frank are undercover agents trying to get a confession from Stan of a murder he committed in Germany. Joanie plays on Stan's love for her, insisting he join the Army and so gain access to the supposed hidden treasure, buried in what is now a U.S. Army reservation. Entrapment is the word used now.