Murder on the Waterfront (1943)

Joey Davis has just been married to Gloria, but before they can have their wedding night, he's called into service in the Navy. He smuggles his new bride into the camp. The camp is under heavy security because the Navy has obtained a new top secret kind of thermostat (and the formula necessary to make it work), which will keep weaponry dry. There is a murder--someone is trying to steal the device, and the newlyweds become involved in the investigation. The major suspect is Gordon Shane with whom the lead investigator has had dealings in the past. The killer has left an essential clue with Gloria, but she doesn't realize it yet. Is Shane the culprit; and if not, can the mystery be solved before the real killer murders Gloria?