In 2016, Carmichael starred in ITV's new television crime drama series, Marcella, as Maddy Stevenson. Marcella focuses on a British Metropolitan police detective and single mother's return to the murder squad, the first English show by Swedish screenwriter Hans Rosenfeldt, who created the Scandinavian television series The Bridge.
In 2016, Carmichael portrayed Muriel Williams in A United Kingdom, a political yet romantic drama, also starring Rosamund Pike and David Oyelowo. The film saw Carmichael immersing herself in the early days of 1940s apartheid. She played Muriel, the sister of Ruth Williams, the Englishwoman who (in real life) challenged colonial racism to marry Seretse Khama, who would become King of Bechuanaland (now Botswana) in 1948.
In 2016, Carmichael played Madam in Jamie Lloyd's production of The Maids at the Trafalgar Studios in London's West End, co-starring Uzo Aduba.