Alistair McGowan is stepping into Rupert Everett's shoes for the last three weeks of the west end show Pygmalion.
The impressionist will play Professor Henry Higgins alongside Kara Tointon's Eliza Doolittle in George Bernard Shaw's play.
The play, which inspired the musical My Fair Lady, is the story of how Higgins, a professor of phonetics, teaches Eliza to speak properly.
Rupert is leaving on August 15 to start filming a new BBC series, Parade's End, set during the First World War and based on the novels by Ford Madox Ford.
Alistair, best known as an impressionist, has also had a successful stage career which has seen him nominated for an Olivier award and work with the Royal Shakespeare Company.