How Endgame actors reacted to the movie's biggest moments

Of the many things that makes Avengers: Endgame stand out — not only from other movies but even other MCU films — is that in many cases, the stars were kept in the dark almost as much as the fans, and for almost as long. Some of the more blatant examples include Mark Ruffalo filming five different endings for Endgame, Tom Holland being denied a script for Endgame because of his penchant for spoiler-dropping, and Letitia Wright not finding out her own character, Shuri, died in Avengers: Infinity War until character posters for Endgame were released shortly before the film's theatrical premiere.

As a result, fans have a unique opportunity to learn the genuine reactions of the movie's stars to the same revelations the audience had to weather. The nature of Endgame meant — whether because of death, retirement, or something else — many of the film's heroes would experience a finality their comic book counterparts almost never get to see (e.g. dying and actually staying dead). With reactions ranging from the emotional to the irreverent, from actors who have walked alongside their character's exploits for a decade in many cases, we have the chance to see just how much these stars grew attached to their parts and how they feel now that — for many, at least — their journeys have either ended or changed drastically.

One of the most crowd-pleasing moments of Avengers: Endgame comes when Tony Stark (Robert Downey Jr.) channels his inner Black Sabbath one last time and says "I am Iron Man" before snapping his fingers and using the Infinity Stones to wipe out Thanos (Josh Brolin) and his forces. It wins the day for the good guys — and it's a powerful sacrifice, as the physical toll of using the Stones is what kills Tony. It's a perfect moment, and one that wasn't in the script. At a Q&A, directors Anthony and Joe Russo said the line was editor Jeff Ford's idea that came up during a discussion about needing a response to Thanos' "I am inevitable." It was added during reshoots — but it almost wasn't, because Downey didn't want to do it.

The Russos brought Downey to dinner to pitch the reshoot, and producer Joel Silver tagged along. According to the Russos, Downey's reaction to his character's death was so powerful he was hesitant to face it again."I don't know. I don't really want to go back and get into that emotional state," they recalled him saying. "It'll take… it's hard." It was apparently Silver — an old friend of Downey's — who changed Downey's mind, responding to the actor's doubts with "Robert, what are you talking about? That's the greatest line I've ever heard! You gotta say this line! You have to do this!"