This film has nothing to do with Robert Louis Stevenson's classic story. Rather this movie is about the World War II naval base called Treasure Island that was located in San Francisco Bay. Set in mid WWII, two code specialists are hard at work trying to decipher Japanese messages and sending confusing messages to deceive the Japanese. However the film is more about the sexual mores of the day than about the wartime effort. It seems each of the coders has a secret. The first is secretly a polygamist, with one wife being Japanese-American that he keeps hidden away so she won't face detention and the other wife being sickly leaving her unable to go out, as well. The other man can only have sex with his wife if another man is watching his performance.