Avengers: Endgame is filled with fist-pumping moments, scenes that left you wide-eyed and weepy, and quotes that you endlessly repeated to friends and family for days on end until they eventually stopped replying to your texts.

But it was perhaps Tony Stark’s finest MCU moment (and greatest quip) that left the biggest mark. However, it very nearly didn’t make it into the movie. As revealed by the Russos themselves, the “I am Iron Man” moment was a last-minute addition, and we have one very unlikely source of inspiration to thank for it.

As reported by /Film, a recent Q&A with the Russos featured a moment where they expanded on the difficulty of nailing Iron Man’s witty retort after he swipes the Infinity Gauntlet from Thanos.

In fact, he originally says nothing but, as the co-directors explain, “We were in the editing room going, ‘He has to say something. This a character who has lived and died by quips.’ And we just couldn’t, we tried a million different last lines.”

But step forward Jeff Ford, the Russos’ right-hand man and editor on Captain America: The Winter Soldier, Civil War, Avengers: Infinity War and Endgame. Not all heroes wear capes – and so it proved with Ford, who suggested “Why don’t we just go full circle with it and say I am Iron Man?”

The idea was so good that the Russos knew they had no time to waste. Their reaction? “We’re like, ‘Get the cameras! We have to shoot this tomorrow.'”

So, instead of Robert Downey Jr. defeating Thanos and not getting a word in edgeways (how weird would that have been?), we now have a neat callback to the MCU’s first defining moment, and a fantastic farewell to RDJ to boot. All it took was one editor. Who says they never do anything useful?

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