11 Comic Book Origins That Were Very Different In The Movies

The prime issue with Ultron's backstory is that it involves Hank Pym - who, at the time of Age of Ultron's release, wasn't yet in the Marvel Cinematic universe, meaning the cyborg's origins had to be altered to not confuse audiences. Pym simply wouldn't have worked in the film's context, as the comics had him create Ultron as a young man, whereas Ant-Man needed the scientist to be introduced to us as an old man.

Both of these things in mind, it makes perfect sense that Ultron's origins were drastically revamped in Avengers: Age of Ultron. Ultron is instead a creation of Tony Stark's, and intended to be a global defense system, instead of just a really clever sentient robot.

Mercifully, the film adaptation also skipped out the vaguely disturbing scenes that featured Ultron desperately trying to gain the affections of his creator and 'daddy' - so there were some definite positives to this decision.