Every so often there is a fan theory that comes along and sticks in your brain. Whether it's a killer idea or one that's so-bad-it's-actually-good, there's usually a case to be made for it to make the jump to our screens.
But that's not the case with this Marvel theory, one that posits the upcoming re-release of Avengers: Endgame will set up Avengers: Doomsday with a subtle piece of post-credits revisionism.
