Inspector Cassin, a renowned Paris detective, departs to the country for a much-needed break. There he falls in love with the innkeeper’s daughter, Nanette, who is already betrothed to a local farmer. On the evening of their engagement party, Nanette and the farmer both disappear. Cassin takes up the case immediately to discover what happened to them and who is responsible.

Jennifer Smith heads a "Consumer Reports"-type company and her reputation for honesty is her greatest asset. While out boating one day she encounters a secret prototype submarine piloted by Bill Craig. Trying to explain her absence after her boat sinks becomes very difficult as Bill and his cohorts attempt to discredit her story.

1944 film by George Cukor