Editor’s note: This post contains mild spoilers for Thor: Ragnarok.

When it was announced that Thor: Ragnarok would pair the flaxen-haired, hammer-wielding Asgardian Avenger with everyone’s favorite not-so-jolly green giant, we were beyond excited. When it was revealed that their buddy comedy would take place halfway across the universe on the planet of Sakaar, our comic book-loving hearts grew three sizes, but our eyebrows raised. How did the Hulk get to space anyway? When we last saw Bruce Banner’s alter ego at the end of Avengers: Age of Ultron, he was flying off into the sunset on a stolen Quinjet to be alone with his thoughts and feelings. As it turns out, the reason is thanks to a behind-the-scenes retcon made by Marvel Studios president Kevin Feige.

In an interview with The Wrap, Feige explained that originally, they weren’t intending on making a Planet Hulk movie, in spite of rumors to the contrary. At one point the script included a bit indicating that they lost the Hulk’s signal somewhere around Saturn, but Feige and company worried this would result in speculation that they were, in fact, sending Hulk to space. As a result, they insisted that director Joss Whedon leave the sky blue at the end of Ultron and mention that they lost signal somewhere over the Caspian Sea.

However, during the development of Thor: Ragnarok, they decided they “wanted to do something totally different with Thor,” according to Feige. For a while, they were even jokingly calling the film “Planet Thor.” Talks amongst the executive team eventually resulted in the fateful decision to pair Hulk with Thor, and to send the dynamic duo to the far-flung planet of Sakaar.

“And this was a year after Ultron came out,” Feige said. “It was kind of a big thing. We were like, ‘You gotta change it Joss, he’s not going to space.’ A year after I go, ‘Joss, guess where he’s going?’ ‘He’s going to space.’”

So, what’s the canonical explanation for how Hulk eventually made his way to become a gladiator in the Grandmaster’s arena? Well, in Thor: Ragnarok, Hulk winds up on the trash planet of Sakaar, which has multiple vortexes in the sky that function as interdimensional garbage chutes, dumping the universe’s refuse on the planet’s surface. It stands to reason that as the Quinjet approached the upper reaches of Earth’s atmosphere, it could have been sucked through one of these vortexes, stranding Banner among the outcasts, misfits, and literal trash people of Sakaar.

Now the big question is how will the Hulk make his way back to Earth for Avengers: Infinity War? Let us know your theories in the comments below.

Image: Marvel Studios

Dan Casey is the senior editor of Nerdist and the author of books about Star Wars and the Avengers. Follow him on Twitter (@DanCasey).

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