Everything You Need to Know Before Seeing Avengers: Infinity War

Marvel Studios

Avengers: Infinity War marks the beginning of the end.

The blockbuster is the first of a two-part conclusion to "Phase Three" of the Marvel Cinematic Universe. With 76 main characters and a 160-minute run time, there is a lot to digest—so a history lesson might come in handy. (Seriously: It'd take 33 hours and 28 minutes to watch the first 18 movies back-to-back, if you exclude the post-credit scenes. And who'd ever skip those?) Luckily, E! News knows the MCU inside and out, so you'll be ready before it hits theaters Friday.

Who Is Thanos—and What Does He Want?

Known to his followers as the Dark Lord and to his enemies as the Mad Titan, Thanos (Josh Brolin) first appeared in 2012's The Avengers. He discovered that the Tesseract was on Earth and hired Loki (Tom Hiddleston) to retrieve it, loaning him the Scepter and his Chitauri army. He "adopted" children, including Gamora (Zoe Saldana) and Nebula (Karen Gillan), weaponizing them for his own gain. He also controls the Black Order: Proxima Midnight (Carrie Coon), Cull Obsidian (Terry Notary), Corvus Glaive (Michael Shaw) and Ebony Maw (Tom Vaughan-Lawlor).

Thanos allied himself with Ronan the Accuser (Lee Pace) in 2014's Guardians of the Galaxy, but the Kree zealot betrayed him in order to use the Power Stone to his own advantage. Ultimately, Ronan's plan backfired—thanks to Star-Lord (Chris Pratt) and his ragtag team of galactic heroes.

In 2015's Avengers: Age of Ultron, the Mind Stone was used to make J.A.R.V.I.S. (Paul Bettany) a sentient being—now known as Vision. In a post-credits scene, Thanos decided to stop hiring minions to do his bidding. With his hand in the Infinity Gauntlet, he said, "Fine. I'll do it myself." If Thanos acquires all six Infinity Stones, he will become the most powerful man in the universe.

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What Are the Infinity Stones—and Where Are They?

• The Space Stone, otherwise known as the Tesseract, controls space and creates portals. It's currently with Loki, who stole it from his late father's vault at the end of 2017's Thor: Ragnarok.

• The Mind Stone imbues powers, as it did for Quicksilver (Aaron Taylor-Johnson) in 2014's Captain America: The Winter Soldier (in a post-credits scene). It's also used for mind control.

• The Reality Stone, or Aether, is a liquid with destructive properties that infected Jane Foster (Natalie Portman) in 2013's Thor: The Dark World. Now, The Collector (Benicio Del Toro) has it.

• The Power Stone can annihilate anyone who touches it and level an entire planet. After the Guardians of the Galaxy seized it from Ronan, they gave it to the Nova Corps for safekeeping.

• The Time Stone was used to trap Dormammu, an evil inter-dimensional entity, in a loop in 2016's Doctor Strange. The titular hero (Benedict Cumberbatch) now wears it around his neck.

• The Soul Stone has yet to appear onscreen, and its location is unknown. Wong (Benedict Wong) warned in Doctor Strange that his ancient texts said it could be the greatest threat of any Stone.

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Why Are Captain America and Iron Man at Odds?

The Avengers do a lot of damage. It's a hazard of the job, and to his credit, Iron Man (Robert Downey Jr.) always spearheaded relief efforts right away. But after Sokovia went poof! in Avengers: Age of Ultron, governing bodies around the world tried to sanction the super-group. For several reasons, Iron Man favored the accords. Captain America (Chris Evans), not so much.

Executing veiled terrorist attacks, Col. Helmut Zemo (Daniel Brühl) manipulated situations that would eventually divide the Avengers. Iron Man led Black Panther (Chadwick Boseman), War Machine (Don Cheadle), Spider-Man (Tom Holland), Black Widow (Scarlett Johansson) and Vision in a battle against Captain America, Falcon (Anthony Mackie), Scarlet Witch (Elizabeth Olsen), Hawkeye (Jeremy Renner) Ant-Man (Paul Rudd) and Winter Soldier (Sebastian Stan). Friends became frenemies, and it was a fight no one but the two leaders really wanted to win.

After Iron Man figured out Zemo's plan, he raced to Siberia to help take him down. But Zemo had another ace up his sleeve: proof that Winter Soldier, under HYDRA's orders, killed Iron Man's parents. Even worse? Captain America knew about it and concealed it from him. After an emotional fight, Captain America surrendered his shield, choosing Winter Soldier over Iron Man. Now a fugitive, he went on to free his imprisoned comrades and help hide Winter Soldier in Wakanda. He also gave Iron Man a private number to reach him at, should trouble ever arise.

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Where Are Thor's Allies?

At the end of Thor: Ragnarok, the surviving Asgardians were loaded on a ship bound for Earth. Heimdall (Idris Elba), The Hulk (Mark Ruffalo) and Valkyrie (Tessa Thompson) barely made it out alive after Hela (Cate Blanchett) decimated their planet. In a post-credit scene, Thor (Chris Hemsworth) and Loki stumbled upon what looked to be Thanos' ship. In trailers for Avengers: Infinity War, the Guardians of the Galaxy found Thor alone, leaving his friends' fates a mystery.

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Will the Avengers Get Back Together?

With a common enemy in Thanos, it's safe to assume the fractured group will team up again.

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Is Thanos Going to Kill One of the Avengers?

Without spoiling anything...probably. Several stars' contracts are up after the fourth Avengers film, including Downey, Evans, Hemsworth and Johansson. Downey and Evans have spoken about wanting to leave the franchise, and Hemsworth has also implied he may be done. Marvel Studios is developing a standalone film for Johansson's character—though it could be a prequel.

"You start to think differently about how the characters are interacting, what character's stories are coming to a close, and what character's stories are only just beginning. Those stories will continue. I think they'll continue in surprisingly different and unexpected ways after these two Avengers films," Marvel Studios president Kevin Feige told Entertainment Weekly. Yes, that could mean death for certain characters—but "that's not necessarily what we're talking about."

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What Happens Next?

Who knows? Even the actors won't know until the fourth Avengers film debuts on May 3, 2019.

But let's not dwell on the future; let's enjoy Avengers: Infinity War. As Pratt explained to E! News' Zuri Hall at the L.A. premiere, "This is the film that every Marvel movie has been leading up to, so it feels very iconic. It feels very epic. The magnitude, the scope, the scale—it's all big!"

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