Jewels of Brandenburg (1947)

Johnny Vickers is a US government agent operating in London. Vickers puts a tail on the double agent Marcel Grandet, with whom he'd worked during World War II. Grandet has during this war a fortune in jewels stolen. With these jewels Grandet intends to finance a neo-Nazi movement. Posing as a fellow fascist, Travis is able to infiltrate the villains. But will Vickers be able to return the stolen jewels and save his own skin?