The Spy in Black

Set in World War I, Captain Hardt (Conrad Veidt) is ordered to take his U-boat to Northern Scotland, where he must contact a fellow conspirator and sink the British fleet. The contact, however, turns out to be a beautiful schoolteacher (Valerie Hobson) who acts as a go-between with the British Navy traitor, Lieutenant Ashington (Sebastian Shaw). The jealousy between the two men over the young woman leads to their plans falling apart, with one of them being left to complete the mission alone.