MCU: 30 Actors Who Could Have Starred In Avengers: Infinity War
22. Emily Blunt (Black Widow)
Emily Blunt has in fact had two near-miss castings in the MCU: she was offered the role of Peggy Carter (Hayley Atwell) in Captain America: The First Avenger but turned it down, and Marvel later offered her the Black Widow (Scarlett Johansson) role in Iron Man 2.
Blunt, however, was locked into a contract with Fox which obligated her to appear in the terrible Jack Black comedy Gulliver's Travels, and as her schedule couldn't accomodate both movies, she was forced to drop out of Iron Man 2.
Would It Have Worked?: Hard though it is to picture anyone but Scar-Jo in that role, Blunt certainly meets the physical and actorly requirements. She's got the beauty, athleticism and sassy appeal, and her American accent's pretty damn great too. It's an emphatic "yes".