When a scientist discovers a way to create synthetic diamonds, a group of criminals kidnap his daughter Meredith (Louisa Braganza) in an attempt to ransom her for the valuable formula. Rescuing Meredith from her kidnappers, the Falcon (Tom Conway) becomes the prime suspect in a string of murders--including that of the scientist. It is then up to the Falcon to prove his innocence by discovering the identity of the true criminals. This film is the last of the Falcon series to star Conway.