Behind the Door (1919)

Oscar Krug is looked upon with suspicion by his neighbors because of his German name. When the U.S. is drawn into the war with Germany, he enlists and travels the seas with his wife, Alice Morse. During a submarine attack, Alice is snatched from Krug's side by a German officer. Krug now lives to have his revenge, and when the opportunity presents itself, he will have it.