when I was young I remember watching a film on bbc2. It was set onboard a ship with a mixed crew of pirates. I have a vague memory of the captain of the ship taking a young couple to get married and during the film all of his crew ends up dying except him. I think at the end the young couple rescue the captain. I have no idea what it was called but I believe it was set around the turn of the last century and there was a German battleship in it.