The Hulk will meet Thanos at the start of Infinity War - and we've got a theory on how he returns to Earth. The ending of Thor: Ragnarok set the stage for Thor, Loki and Hulk to truly kick off the events of Marvel's Infinity War. Drifting through space with what remains of Asgard, the mid-credits scene caused the hopeful mood to evaporate completely, as Thor and Loki stared at a massive ship suddenly arriving in their path. A ship now confirmed to be Thanos and his Black Order's vehicle.

What happens next is both generally revealed in the trailers, and a bit of a mystery. We know that Thanos gets the Space Stone from Loki after he swiped it from Odin's Vault, and we know that Hulk ends up across the galaxy, smashed directly into the Sanctum Sanctorum of Doctor Strange. Back in the form of Bruce Banner, no less. So... what are the trailers leaving out?

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We have our own Infinity War Theory to fill in the missing pieces, answering how Hulk gets from Thor's ship to Earth. But that's just the start of the questions it raises, the second being: why is Hulk no longer in control of Banner's body (which the good doctor feared would be the case after transforming in Thor: Ragnarok)?

Most importantly, we're betting that Hulk escaping from Thanos is what cements Loki's ascendance to a true Hero in the MCU.

Loki Uses The Space Stone To Send Hulk To Earth

Since the first Infinity War trailer showed Doctor Strange and Wong leaning over the smashed staircase of the Sanctum Sanctorum, and beholding Bruce Banner in the crater, fans have been speculating. Was Hulk knocked to Earth from wherever Thanos attacked, falling back into the MCU while Thor floated until found by the Guardians of the Galaxy? Some have even wondered if the object entering Earth's atmosphere in a glowing ball of fire in the latest Infinity War trailer was Hulk on re-entry. But as in most cases, the correct answer may be the simplest one.

We know that Loki has the Space Stone-- or the Tesseract, as it was referred to until Thor learned the true nature of the Infinity Stones. The Tesseract has already been shown to operate as a "doorway," bringing Loki to Earth in The Avengers, and later, the Chitauri army commanded by Thanos. So when Thanos's ship arrives in the mid-credits scene of Ragnarok, Loki and Thor presumably have an escape route... even if Thor isn't entirely aware that Loki 'rescued' the Cube from Odin's Vault.

The question one might ask - or the first question, at least - is why send Hulk to the Sanctum Sanctorum of Doctor Strange? And Ragnarok may have provided that answer earlier. Loki was given a less-than-warm welcome to both the Sorcerer and his Sanctum earlier in the movie. Technically, it was Thor who got to officially pay a visit to both occupant and residence, while Loki's time there amounted to seconds. Just long enough to complain about his treatment, draw daggers in pursuit of some payback, and be swallowed up by a portal.

It's possible that was enough. A god of mischief like Loki knows powerful sorcery when he meets it, and even if he would never admit it, Doctor Strange completely outplayed and overpowered him. He may be the only Marvel character to ever get the better of Loki on magical or mystical terms, which shouldn't be overlooked. And if Loki put any time into understanding the Infinity Stones driving the events of Thor, Odin, and Asgard over the past few years, it's plausible he knew what the arrival of Thanos meant, just as much as Thor.

Which means he knew exactly what he was doing when he chose NOT to follow. Needless to say, explaining that part requires some serious potential SPOILERS...

Loki Saves Hulk - And Sacrifices Himself To Thanos

The best solution? Send the strongest among them ahead to Earth as a warning. And whether Hulk goes willingly or not, Loki may know exactly how to use the Space Stone to deliver someone across the galaxy... into the sky around the rough vicinity of the target. The universe is a big place. And yes, we know what you're all wondering: why didn't Loki go with him? That question points to the real meaning of the scene, since it makes Loki an undeniable hero in the MCU - even if his time in it comes to an end.

As easy as it would be to look at the trailer shots of Loki surrounded by the Children of Thanos and assume that he, like Thor, has fallen victim to the villain's Infinity War plan, that's not the whole story. It's been years since this point, and feels like even linger, since Loki first returned from the dead to wage war on the newly-formed Avengers. Doing so with not one, but TWO Infinity Stones that should have returned to Thanos's grasp by the end of the mission. Loki failed, and broke the deal. And until now, has somehow stayed one step ahead of paying the piper.

And so we arrive at the point Ragnarok ends, and Infinity War begins. Thanos beginning his attack on the remaining Asgardians, apparently showing Hulk "what damage he can cause" - demonstrated by the slaughtered bodies visible in every shot of the encounter. Bodies of Asgardians, which is why Thor wouldn't retreat from the fight. And neither will Loki. As we've outlined in a previous theory, that's the reason Loki stays behind to fight and be executed by Thanos.

The Perfect Ending To Loki's Character Arc?

The Loki that fans knew from the first two Thor movies, and the Avengers (and maybe even the one seen through most of Ragnarok) would never pass such a clean escape off to Hulk. Nor would he stand his ground and face the punishment that he hath wrought by dealing with Thanos. Some might say that such a sacrifice is pointless, but we would argue that depends on just how far into the fight Loki or Thor realize that sending word ahead to Earth's Avengers is crucial. Thor wouldn't take the job, so perhaps in his final stand, Loki finally decides to follow the same heroic path as his older brother.

It would explain why Hulk winds up fighting in the third act battle at Wakanda, while adding a twist in the fact that he now fights to honor the death of the "puny god" he once walloped. As for Thor, well... nothing would be more tragic than seeing his brother become the reluctant hero he knew he could, only to be killed for it. Would it justify Thor seeking out a new weapon to take vengeance on Thanos? Absolutely. Would it give satisfying closure to one of the most popular MCU characters, while making good on Kevin Feige's warning to "be careful what you wish for?" In the cruelest fashion, yes.

Even fans have criticized Loki's large role in Thor movies as taking away from the hero's. But to see him truly ally with Thor, only to be killed when the heroes might need him most? That's a truly devious plot twist (in the best way possible, from the overall MCU's perspective).

Hopefully, Bruce Banner will get to explain to all of the Avengers how Loki saved his life by giving his own all at once. Considering the last time they saw Thor's brother... that might take some time to process.

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