That's where the fan theories come in. Titanic is a whopping three hours long, giving redditors ample room to come up with far-fetched, but somewhat compelling, ideas. But there's one theory that fans have been convinced of for ages: Jack could've fit on that door! Recently, James Cameron, the movie's director and resident dream squasher, confirmed in an interview with Vanity Fair that there was room for one person, and one person only, on the door.