In 2019, Atwell starred opposite Tamara Lawrance in a three-part BBC adaptation of Andrea Levy's novel "The Long Song", about a slave on a sugar plantation in 19th-century Jamaica. She also reprised the role of Peggy Carter in '. In September 2019, it was announced that Atwell will star in ' and , both directed by Christopher McQuarrie and scheduled to be theatrically released in the United States on 19 November 2021 and on 4 November 2022, respectively. In 2021, early reviews for "" revealed Atwell as part of the film's voice cast as Mittens the cat.