Black Widow (Scarlett Johansson) first appeared in MCU films beginning with Iron Man 2 in 2010. It sadly takes more than a decade for a solo movie about this beloved superheroine to come up, especially after her death in The Avengers: Endgame.
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@ Black Widow is scheduled to be released in the United States on May 7, 2021, as the first film in Phase Four of the MCU.