Avengers: Infinity War is going to be the biggest crossover event that the Marvel Cinematic Universe has ever seen - the culmination of a decade of storytelling on the big and small screens. However, the events of Infinity War aren't just built off the stories of the MCU; like so many things in Marvel's live-action universe, they were inspired first and foremost by things that happened in Marvel Comics.
Given the expansive nature of Infinity War and all of the various characters and franchises it brings together, there are actually a handful of famous Marvel Comics storylines clearly at work in the film. Read below for a breakdown of the biggest and most prominent Marvel Comics stories that are influencing Infinity War:
1 - "Infinity Gauntlet"
This is the most obvious connections between Infinity War and the comic books. Jim Starlin, George Pérez, and Ron Lim's 1991 miniseries brought Thanos center stage in the Marvel Universe for the story of how The Mad Titan collects the six Infinity Gems together to form the all-powerful Infinity Gauntlet. With the Gauntlet, Thanos wreaks havoc on the entire reality of the Marvel Universe, wiping out half of all life in the cosmos and slaughtering droves of Marvel superheroes that rose up to oppose him.
It remains to be seen if Thanos will actually unite all the MCU Infinity Stones and manifest the full power of the Gauntlet in Infinity War. But even if the film doesn't fully follow the comic book storyline, there's plenty of room for Avengers 4 to deliver the full cosmic mayhem from the original storyline.
2 - "Infinity"
This 2013 storyline from Jonathan Hickman sees a two-pronged storyline where Thanos and his Black Order attack Earth while the Avengers are away in space dealing with another threat. It culminates with the Avengers rushing back to Earth and splitting into smaller teams to free Earth from the various members of the Black Order in order to shut Thanos down.
It's clear from The Infinity War trailer that the outline of the "Infinity" storyline has been refitted to serve as the basic premise of the Avengers: Infinity War film. Thanos and the Black Order attack Earth on various fronts, looking to gather the various Infinity Stones that are hidden on the planet. Some of the Avengers will be off in space and need to rush home (Thor, Star-Lord, Hulk), others will need to emerge from seclusion (Captain America, Black Widow, Winter Soldier) and some will need to defend themselves when the threat arrives on their doorstep (Doctor Strange, Vision, Black Panther).
3 - "Secret Avengers"
This Avengers comic book series of the 2010s saw Steve Rogers operating a covert Avengers team that handled secret missions while the main Avengers squad did the public acts of heroism.
From what we've seen of Captain America's arc in Avengers: Infinity War, Cap's "Nomad" era will be combined with his "Secret Avengers" phase. Based on some clever Easter eggs, we already know that Tony Stark has been keeping contact with Steve Rogers since the events of Captain America: Civil War, calling in Cap and his espionage-trained team (Black Widow, Hawkeye, Falcon) when the situation warrants it.
Avengers: Infinity War opens in theaters on May 4, 2018. Other upcoming Marvel Cinematic Universe movies include Black Panther on February 16, 2018, Ant-Man and the Wasp on July 6, 2018, Captain Marvel on March 8, 2019, the fourth Avengers movie on May 3, 2019, the sequel to Spider-Man: Homecoming on July 5, 2019, and Guardians of the Galaxy Vol. 3 in 2020.