The star was originally set to feature in the Marvel Cinematic Universe, with a role in 2013's Iron Man 3.
In fact, she was at an early table read, co-writer Drew Pearce revealed on Instagram.
"My finest hour: at an early Iron Man Three table read," he wrote, sharing a throwpack picture from 2012.
"Downey, Cheadle, Emilia Clarke (long story, the script changed)... all vaguely terrifying."
It's unclear what part Clarke was supposed to play or how the script was altered. But we do know Clarke's involvement in the movie wasn't the only thing that drastically changed over time.
Iron Man 3 star Rebecca Hall and director Shane Black both previously confirmed that Hall's character Dr Maya Hansen had a much larger part in the original script, but the part was cut down because Marvel didn't think a female toy would sell.
Hall said in 2016: "Halfway through shooting they were basically like, 'What would you think if you just got shot out of nowhere?' I was meant to be in the movie until the end..."
Meanwhile, Clarke explained that she turned down starring in the Fifty Shades series because she had concerns over being "pigeonholed" for the rest of her career.
"The last time that I was naked on camera on [Game of Thrones] was a long time ago, and yet it is the only question that I ever get asked because I am a woman," she said.
"And it's annoying as hell and I'm sick and tired of it because I did it for the character – I didn't do it so some guy could check out my tits, for god's sake."
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