Fans have been coming up about theories about the Marvel Universe ever since it first started and now a new Marvel fan theory suggests that the villain of the fifth Avengers movie could be none other than one of the most lovable characters, Hulk himself.

The theory is based on a comic book run called World War Hulk, in which the character became resentful towards his former allies such as Tony Stark and Doctor Strange, and vowed to take them down. For the uninformed, in the Marvel Cinematic Universe, Bruce Banner aka Hulk interacted with both Tony and Dr. Stephen Strange multiple times.  

The theory which was posted on Reddit, suggests that Bruce's reaction would be after losing Natasha Romanoff in Avengers: Endgame and having Tony take the credit for defeating Thanos while his contributions being forgotten. The theory speculates that combined with the loss of Natasha and the resentment he feels towards Tony because of the events that took place in Avengers: Endgame, Bruce might transform into a villainous character in Avengers 5.

Avengers writers Christopher Markus and Stephen McFeely recently revealed that Bruce might not be as in control of his Hulk persona as he claims he is. They said that after snapping his fingers, he was transported to the Soul World, where he Smart Hulk came face to face with Bruce. The duo said, "We did write one, a conversation between Hulk and Banner, but it didn’t make it to the camera. Ruffalo showed up but Hulk wouldn’t come out of his trailer."