One popular fan theory suggests that Jack Dawson could have been a time traveler in Titanic. Leonardo DiCaprio's Jack Dawson was a complete mystery throughout Titanic, sweeping Kate Winslet's unhappy Rose off her feet in a mad love affair that lasted only a matter of days before the Titanic's infamous crash. James Cameron's classic film skyrocketed the leading actors to lifetimes of success, but their Titanic characters could have had many secrets that weren't revealed in the chaos. However, little hints throughout could point to the romantic Jack being a man out of time.

The theory uses several inconsistencies in Titanic as evidence for the idea that Jack Dawson was in fact a time traveler, perhaps sent back from the future to save Rose. One other theory offers some of the same evidence to support the idea that Titanic's Jack didn't exist at all, which is just as outlandish,...