(Obviously, there are a ton of spoilers ahead for the end of "Avengers: Infinity War." Read on at your own risk, if you're someone who has both not seen the movie yet still cares about spoilers.)
Everyone who saw the ending of "Avengers: Infinity War" is wondering where the Marvel Cinematic Universe is going to go in "Avengers 4."
The fateful cliffhanger found Thanos (Josh Brolin), the big bad guy that the MCU has teased for six years, finally making his way to Earth in search of the Infinity Stones. Just about all the heroes of Marvel's universe turned up to oppose the Mad Titan's plan: Gather the all-powerful stones into his weapon, the Infinity Gauntlet, and use them to near-instantly wipe out half of all life in the universe.
"Infinity War" ends with Thanos finally getting the final stone, the Mind Stone, and snapping his fingers -- accomplishing his goal and causing half of everyone everywhere, including the MCU's heroes, to turn to dust and disappear. Fans have been wondering just how the MCU will deal with that situation, and the still-alive Thanos, in "Avengers 4." But like the coming of Thanos, it's possible the MCU has been teasing a solution, and a larger look at its universe, all along. The last clue came in "Infinity War" itself, with the short appearance of one of Marvel's weirdest characters: The Collector.
In the MCU, the Collector (Benicio del Toro) is a strange man who does as his name suggests -- he collects everything he can. In the Marvel comics, though, the Collector is a lot more fleshed out. He's one of a small group of powerful, immortal and nearly invulnerable beings called the Elders of the Universe, each of which is the sole surviving member of the oldest civilizations in the universe.
Fans of the comics know the significance of the Collector, but so far, he's only enjoyed small-scale appearances in the MCU movies -- he was in the post-credits scene of "Thor: The Dark World," when Thor (Chris Hemsworth) brought him the Reality Stone (AKA the Aether) for safekeeping. And he had a couple scenes in the middle of "Guardians of the Galaxy," with the Guardians trying to sell him the Orb, which housed the Power Infinity Stone.
The Collector appears in "Infinity War" as well, although it's not really him. When the Guardians reach Knowhere to try to get the Reality Stone from the Collector before Thanos, they find Thanos threatening him and beating him up and stuff. But it turns out the Collector isn't really there -- it's all a ruse by Thanos, using the Reality Stone to capture Gamora (Zoe Saldana). The fate of the Collector is unknown, but we think it's extremely likely that Marvel didn't kill him off-screen after what amounts to a cameo appearance.
Instead, it seems like the MCU is building up to something with the Elders. The Collector isn't the only one to show up in the MCU so far -- the Grandmaster (Jeff Goldblum), one of the antagonists in "Thor: Ragnarok," is also one of the Elders. He runs a big gladiator arena on Sakaar in "Ragnarok," and his deal is big, involved games. He's also best friends with the Collector in the comics.
So there are two super-powerful, super-old Elders of the Universe hanging around as Thanos goes gathering his Infinity Stones, and one of them loves games. In the comics, the Grandmaster has created cosmic-scale games more than once that use the Avengers and other heroes as pawns. Once, the Grandmaster even used Earth heroes in a game against Death -- to get Death to resurrect the Collector after his death.
There's some evidence a game could be afoot in "Infinity War," and it has to do with what Doctor Strange (Benedict Cumberbatch) sees when he looks into the future on Titan. Strange makes sure to tell Tony Stark (Robert Downey Jr.) that if things should come down to protecting the Time Stone or protecting the heroes, the Time Stone comes first. But when the moment comes, Strange trades the Time Stone to save Tony's life, at odds with exactly what he said he'd do.
We repeatedly see other heroes do the same thing: Gamora gives up the Soul Stone's location to save Nebula (Karen Gillan) and Loki (Tom Hiddleston) trades the Space Stone to save Thor. Add to that Vision (Paul Bettany) and Captain America (Chris Evans) repeatedly telling each other "we don't trade lives," and we get a clear ethos from the heroes: They won't sacrifice people. That's exactly at odds with Thanos, who sacrifices Gamora and, indirectly, all his lieutenants to get the stones.
Strange changed his plan once he looked into the future, specifically giving up the Time Stone after saying he wouldn't. That would make sense -- if Strange realized the fight with Thanos was actually part of a larger game and winning it required a long view and change in tactics. And it seems weird that "Infinity War" would just drop the Collector into the movie for what amounts to a quick cameo, unless there's more to his story.
If that's the case, then the ultimate conclusion of the Thanos battle could hinge on impressing the Collector (and maybe the Grandmaster) and winning the game, rather than beating Thanos. That would provide a way to undo Thanos' universe-wrecking snap, and give the heroes a way of beating Thanos without actually having to fight the Mad Titan, since they've proven they might not be able to beat him while he has the Infinity Stones.
We've spent a lot of time over the past few weeks digging through the details to try to figure out what's coming not just in "Avengers 4" but also "Captain Marvel" and "Ant-Man and the Wasp." We have come up with a pretty solid guess about what is involved in the one future Doctor Strange saw in which the Avengers defeat Thanos. Click here for our deeper look into how "Captain Marvel" might impact that distressing plot twist. at the end of "Infinity War." Click here for our look at what "Ant-Man and the Wasp" might have to do with all this. Click here for our discussion of the whole Vision situation and whether he's really dead. Here's our run-down on how the comic book version of these events played out. And here's the evidence that suggests who else could be behind a cosmic test at the heart of "Infinity War." Finally, while we're talking about fan theories, here are a few of the most plausible -- and a bunch of the wildest.