'Why? Why does Jack choose to die for Rose when there was plenty of room on the raft for both of them?'

It's the question that's been burning since we first balled our eyes out in front of Titanic in the cinema in 1997. Not to spoil the ending but when the ship begins its descent into the icy sea, leaving its passengers fighting for their lives in the sub zero ocean, Leonardo Di Caprio's character Jack makes a very odd decision. Ever the gent, he rolls off the floating door the pair are using as a raft, leaving Rose (Kate Winslet) on top of it. Very chivalrous, obvs, but a touch short sighted, given the seemingly needless gesture results in his death. in 2013, Mythbusters dedicated an entire episode to the subject, deciding that, in their view, the door raft would have been buoyant enough to support both Jack and Rose together. Initially, director James Cameron, who appeared on the episode, agreed the Mythbusters team were probably right. Now however, he appears to have changed his tune. Speaking to The Daily Beast, Cameron says: 'Look, it’s very, very simple: you read page 147 of the script and it says, “Jack gets off the board and gives his place to her so that she can survive.” It’s that simple. You can do all the post-analysis you want.' 'OK, so let’s really play that out: you’re Jack, you’re in water that’s 28 degrees, your brain is starting to get hypothermia. Mythbusters asks you to now go take off your life vest, take hers off, swim underneath this thing, attach it in some way that it won’t just wash out two minutes later—which means you’re underwater tying this thing on in 28-degree water, and that’s going to take you five to ten minutes, so by the time you come back up you’re already dead. So that wouldn’t work. 'His best choice was to keep his upper body out of the water and hope to get pulled out by a boat or something before he died. They’re fun guys and I loved doing that show with them, but they’re full of shit.' Mystery solved.