From Hawkeye's big switch to Natalie Portman's lost scene: 'Avengers: Endgame' writers reveal major changes made along the way

Warning: Major Avengers: Endgame spoilers below.

Avengers: Endgame is a triumph, both as an extremely satisfying conclusion to the Marvel Cinematic Universe's 22-film arc that started with 2008's Iron Man, and as a record-shattering box-office behemoth of an event movie. As of Friday, the film was the second highest-grossing movie ever worldwide, and breathing down the neck of all-time champ Avatar.

The crafting of Endgame was not just years in the works — as co-writers Christopher Markus and Stephen McFeely note, they started outlining both last year’s Avengers: Infinity War and Endgame in late 2015 — it went through extensive rewrites during pre-production, and significant reshoots (er, "additional photography") following test audience reactions. Further complicating matters, the films were shot back-to-back, so post-production tweaks made to Infinity War would have ripple effects in Endgame.

Some scenes were moved from one film to the next. Most notably, Marvel's pre-eminent wordsmiths Markus and McFeely revealed to Yahoo Entertainment in an extensive interview (watch above), was the opening scene to Endgame, in which Clint Barton, aka Hawkeye (Jeremy Renner), watches in horror as his family disappears as a result of Thanos's fatal snap.

"That was written to be the end of Infinity War," McFeely explained. "So that snap would happen, Thanos would go to the ethereal world and talk to Gamora, and you'd come back and you'd be on some farm you hadn't seen in many movies, with a character you hadn't spent any time with in the last two-and-a-half hours. His family would disappear, then you'd come back to Wakanda and see those people disappear. You'd go to Titan and see those people disappear.

"I think early on in editing [Infinity War], it was clear that we were going to move that to the next one. And I didn't realize how well that would work. [Hawkeye’s] family would disappear, then when he comes back you know exactly what's in his heart, you know why he's a rageful psychopath and killing people."

We were also going to meet Professor Hulk (or as the writers call him, “Smart Hulk”) — the man-beast blending the best of the green goliath and human alter ego Bruce Banner (Mark Ruffalo) — at the end of Infinity War. “If you remember, over the course of [Infinity War], Banner can't get along with the Hulk. Hulk won't come out. And eventually they make a compromise, and then Smart Hulk rips out of the armor and wins the day by doing something powerful and smart. And then he turns around and Natasha shows up and he says something erudite and we go, ‘Oh, this is a different Hulk.’”

Added Markus: "It was like we kicked off a different movie right at the end of that one. But it created a problem because in that we had already shot most if not all of Endgame, whereas he was already Smart Hulk, there wasn't an explanation for why he was Smart Hulk."

In Endgame, Hulk was initially going to have a big hero moment prior to the scene in the diner where it becomes clear his celebrity status has exploded in the five years since the Snapture. "[He] was actually saving people from a burning building," Markus said. "Like a very straight-up almost Superman scene. We wanted to show this guy people used to view as a monster is now the last remaining superhero. And it was fun but it didn't give you anything that diner didn't give you."

As for the time travel, Tony (Robert Downey Jr.), Steve (Chris Evans) and company did not originally quantum leap their way back to the Battle of New York that ended 2012's The Avengers. "Our first draft, we did not go to The Avengers movie, we did not go to New York, 2012. We went to went to separate missions that involved the Triskelion [a major location in Captain America: The Winter Soldier], sort of sneaking into the back door of Kamar-Taj [Doctor Strange], and then going to Asgard.

“Tony ended up going to Asgard — he's wearing a stealth suit so he's invisible and Heimdall [Idris Elba] can see him because you can't get one past Heimdall. And they fight, and it doesn't go well.”

Ultimately it was Thor (Chris Hemsworth) and Rocket (Bradley Cooper) who travel to Asgard in Endgame. And there was originally a longer scene planned between the latter and fan favorite Jane Foster (Natalie Portman).

"We actually wrote scenes between [Jane] and Rocket," said Markus. "It was spending a lot of time with two people who didn't need the screen time for the closure that we needed. We needed to put it all on Thor, and keep that very light." (The writers confirmed Portman did not shoot any additional footage for Endgame; her scene was crafted from unused footage from Thor: The Dark World, with Rocket added via CGI.)

Among the other nuggets the writers revealed: At the beginning of Endgame, Steve Rogers would be struggling with his relationship with live-in girlfriend Sharon Carter (Peggy Carter’s niece played by Emily VanCamp in The Winter Soldier); there was discussion about bringing back Vision (Paul Bettany), but the writers hinted that the story will be handled on the upcoming Disney+ series co-starring Elizabeth Olsen as Wanda Maximoff/Scarlet Witch; and Tony Stark’s death scene would mirror Thanos’s post-snap scene from Infinity War, with Tony going to the “ethereal world” and having a conversation with the adolescent version of his daughter Morgan, played by Katherine Langford.

Watch our full interview below for even more Endgame tidbits from Markus and McFeely.

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