Before Anthony and Joe Russo began directing movies for Marvel Studios, they were executive producers of NBC's comedy series Community - which coincidentally predicted the plot of Avengers: Infinity War eight years before it was released. In one of Community season 2's end credits scenes (another thing the show has in common with the Marvel Cinematic Universe), Troy and Abed do some improv storytelling that includes a giant spaceship, aliens, mercenaries, romance - and more.
Community was created by Dan Harmon and produced through his joint production company with the Russo brothers. It ran for six seasons (though not, as yet, a movie) and was packed with pop culture references and homages, including episodes featuring high-stakes games of paintball and one that explored the possibility of alternate universes. Both Troy (Donald Glover) and Abed (Danny Pudi) have also appeared in the MCU, with Glover playing a helpful criminal in Spider-Man: Homecoming and Pudi playing a SHIELD officer in Captain America: The Winter Soldier. Community actors Jim Rash, Ken Jeong, and Yvette Nicole Brown have also popped up in the Russos' MCU movies.
In the ending tag for Community season 2, episode 9, "Conspiracy Theories and Interior Design," Troy and Abed are playing a one-word-at-a-time game that Troy quickly becomes bad at when he becomes too engrossed in Abed's storytelling. With a little help from Troy, Abed comes up with a story about, respectively, a big spaceship, aliens, mercenaries, war, betrayal, romance, and karate.
Avengers: Infinity War, of course, opens with a big spaceship - the Sanctuary II - ambushing the Asgardians, before another big spaceship, the Q-Ship, arrives on Earth and unleashes aliens. Fortunately, Thor is rescued from where he's floating in space by a group of mercenaries, the Guardians of the Galaxy. With Thanos' plan to gather all the Infinity Stones and wipe out half the universe revealed, the Infinity War begins on two fronts, with some Avengers gathering for battle in Wakanda while others team up with the Guardians on Titan.
There's plenty of betrayal: Loki's fake-out betrayal at the start of the movie; Gamora giving up the location of the Soul Stone; Doctor Strange handing the Time Stone over to Thanos; and Thanos throwing Gamora off the cliff at Vormir in order to obtain the Soul Stone. There's a half-hearted romance subplot featuring Wanda and Vision and as for the karate - well, there's enough fighting that someone probably pulls a karate move at some point.
So, it turns out that Troy was right: he and Abed really should have written a screenplay together, because off-the-cuff they came up with a storyline for a movie that made $2 billion at the box office. Cool. Cool cool cool.