Benedict Cumberbatch, as it turns out, improvised one of the biggest moments in Avengers: Endgame. This, according to Doctor Strange director Scott Derrickson, who recently made the reveal on Twitter. Had Cumberbatch not improved the moment as we saw it on screen, the climax of the movie may well have felt quite a bit different and, perhaps, not made as big of an impact.

The moment in question comes during the climactic battle at the end of Avengers: Endgame. The heroes are wrestling to keep the Infinity Stones away from Thanos and his goons, with the fate of the universe hanging in the balance. Doctor Strange, at a key moment, then holds up a finger to Robert Downey Jr.'s Tony Stark, indicating that they are in the midst of the one scenario that they won out of more than 14 million future Strange had visited in Infinity War. On Twitter, a fan shared a gif of this moment, which Scott Derrickson retweeted, revealing that the moment was not planned as such. Here's what Derrickson had to say.

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"Benedict told me this moment was an improv."

It is a truly massive moment within the framework of the Marvel Cinematic Universe. The stakes could not have been higher. It serves not only as a callback to the key moment in Infinity War, but it also helps set up the sacrifice to come. Tony ultimately gives his life to stop Thanos, putting on the gauntlet himself to snap the Mad Titan and his followers out of existence. The single finger also harkens back to a key line earlier in the fight when Strange says to Tony, "If I tell you what happens, it won't happen." Strange only clued Iron Man at the pivotal moment with the simple yet powerful gesture.

Scott Derrickson ushered Benedict Cumberbatch into the MCU with 2016's Doctor Strange. The movie was a success, earning praise from critics and fans on its way to $677 million at the box office. Cumberbatch has since reprised the role several times in Thor: Ragnarok, Infinity War and Avengers: Endgame. The actor is gearing up to make his return alongside Tom Holland's Peter Parker in Spider-Man 3, which is gearing up to begin filming. Cumberbatch will then finally suit up for a solo sequel, Doctor Strange in the Multiverse of Madness. Derrickson was originally going to return to the director's chair but creative differences with the studio led to his departure. Derrickson will remain on board as an executive producer, with Sam Raimi (Spider-Man, The Evil Dead) directing.

Improv or no improv, things worked out extremely well for Avengers: Endgame. The movie, directed by Joe and Anthony Russo, went on to overtake Avatar as the highest-grossing release in history. We will next see Benedict Cumberbatch as the Sorcerer Supreme in the untitled Spider-Man 3 on December 17. 2021, with Doctor Strange in the Multiverse of Madness set to follow on March 25, 2022. You can check out the original post from Scott Derrickson's Twitter.