In 1955 Carmichael was noticed by the film producers John and Roy Boulting, who cast him in five of their films as one of the major players. The first was the 1956 film Private's Progress, a satire on the British Army; he received critical and popular praise for the role, including from the American market. In many of his roles he played a likeable, often accident-prone, innocent. In the mid-1960s he played Bertie Wooster in adaptations of the works of P. G. Wodehouse in The World of Wooster for BBC Television, for which he received mostly positive reviews, including from Wodehouse. In the early 1970s he played another upper-class literary character, Lord Peter Wimsey, the amateur but talented investigator created by Dorothy L. Sayers.
In 1955 Carmichael was noticed by the film producers John and Roy Boulting, who cast him in five of their films as one of the major players. The first was the 1956 film Private's Progress, a satire on the British Army; he received critical and popular praise for the role, including from the American market In many of his roles he played a likeable, often accident-prone, innocent. In the mid-1960s he played Bertie Wooster in adaptations of the works of P. G. Wodehouse in The World of Wooster for BBC Television, for which he received mostly positive reviews, including from Wodehouse. In the early 1970s he played another upper-class literary character, Lord Peter Wimsey, the amateur but talented investigator created by Dorothy L. Sayers.