I know this story well. My mothers Cousin in Norway was married to a Norwegian Navel officer who was the son of the ferry boat captain in the movie.His father was the actual captain, not the actor. I watched this movie many times over the years and never knew about that. My mother and father went over to Norway to meet my mothers cousin there and they were told the story. Amazing ! Kirk Douglas looks the part. Great movie to watch on a Cold Sunday afternoon in January.