Here are all the Marvel Cinematic Universe movies fans should catch up on before going to see Avengers: Endgame, according to the film's writing duo. It's no exaggeration to say that last year's Avengers: Infinity War saw a seismic shift in the MCU franchise, as Thanos achieved his goal of collecting the Infinity Stones and wiping out half of all life in the universe. As the likes of Bucky Barnes, Spider-Man and Nick Fury turned to dust, cinema-goers were left reeling as they walked out of theaters, facing an agonizing year-long wait until the continuation of the story.

After a full twelve months of speculation as to how the remaining Avengers could possibly beat Thanos, some theories considerably more colorful than others, Endgame has almost arrived and fans are rapidly running out of time to catch up on the decade of MCU movies released previously. Because while some will be content to go into Endgame fresh from last month's super successful Captain Marvel, others will want to refresh their memories of previous major franchise installments.

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In a conversation with Screen Rant, Endgame screenwriters Christopher Markus and Stephen McFeely helpfully list the movies they believe fans should familiarize themselves with before the second round against Thanos later this month. The writers state:

Robert Downey Jr as Tony Stark in Iron Man

Christopher Markus: Well, but I would say you have to pay to rent all three Captain America movies.

Stephen McFeely: Right. That’s right.

Christopher Markus: And then for the Thanos backstory, I find his family relationship fascinating so I guess the Guardians [films]. And Iron Man 1.

It's strange that neither man mentions the previous three Avengers movie (perhaps that's just a given) but nevertheless Markus and McFeely's selection certainly throws up some interesting picks. The likes of Captain America: The Winter Soldier, Civil War and the two Guardians of the Galaxy movies perhaps won't come as too much of a surprise given their importance to the franchise, but the first Captain America and Iron Man adventures are very interesting choices. Why would fans need to re-watch these prior to Endgame?

The inclusion of these two older movies could be seen as further evidence that Endgame will see the Avengers traveling back in time to key events in previous movies - a widespread fan theory supported by on-set photos. Could the origins of Cap and Stark be meddled with in an attempt to change the future? The writers' Iron Man recommendation could also add fuel to the "Tony Stark is going to die" fire, with many speculating that Endgame will be Robert Downey Jr.'s final MCU appearance. Alternatively, the Endgame trailer shows Tony Stark stranded in space with only an angry blue Luphomoid for company. Will his escape directly connect to the genius billionaire playboy philanthropist's miraculous cave breakout in the very first MCU movie?

Clearly, Markus and McFeely aren't going to reveal anything that will provide even the smallest hint towards the plot of Avengers: Endgame but, frustratingly, the unusual choices have to mean something and, just like the rest of the film's marketing campaign, will have fans speculating right up until release day.

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