Post-war work
Back in London Grenfell wrote the song "Du Maurier" (music by Addinsell) and the monologue "Travelling Broadens the Mind", both of which she performed in Noël Coward's first post-war revue, Sigh No More (1945). Coward had been a family friend since Grenfell was a girl. At first he had viewed her transition from amateur to professional with some doubt. Within a few years he had come to recognise her professionalism, her skill as a performer ("good in all she does on the stage") and the quality of her monologues, even if "she shouldn't write lyrics." In addition to her own two numbers, she sang Coward's comic catalogue of domestic disasters "That is the End of the News", "disguised as a schoolgirl with pigtails, all my make-up off, a shiny face and a terrible grin."
After the 1947 revue Tuppence Coloured, Grenfell developed new sketches including the first of her six Nursery School monologues, with the harassed teacher's recurring cry to one of her unseen charges, "George – don't do that...." In the 1951 revue Penny Plain she performed her "Joyful Noise" (music by Donald Swann), a parody of an amateur choir ("And some of us cannot sing much, And some can't sing at all, But how we love our outings to the Royal Albert Hall"). After this, Grenfell and Tunnard made another tour entertaining British troops in North Africa.
Joyce Grenfell Requests the Pleasure (1954) was her first more or less solo West End show (there were three dancers providing interludes between Grenfell's numbers). The Stage commented that any doubts that Grenfell could sustain a solo evening were quickly dispelled:
After two provincial tours and a year in London she took the show to Broadway, where it had a sell-out eight-week run. For this show there was a pit band of eight players directed by William Blezard. In later shows Grenfell simplified the format further, dispensing with dancers and band, and being accompanied only by Blezard at the piano.
During the 1950s and 1960s Grenfell appeared in several film roles including "Lovely Ducks", the shooting gallery attendant in Stage Fright (1950), Miss Gossage in The Happiest Days of Your Life (1950), Police Sergeant Ruby Gates in the St Trinian's series, Mrs Barham in The Americanization of Emily and Hortense Astor in The Yellow Rolls-Royce. Away from the theatre, Grenfell served as a member of the influential Pilkington Committee on Broadcasting from 1960 to 1962, and was president of the Society of Women Broadcasters and Writers.
The rest of Grenfell's stage career was in a series of solo shows in London and on tour. Between 1957 and 1970 she gave her show Joyce Grenfell in Australia, Canada, Hong Kong, New Zealand, Singapore, Switzerland and the United States, as well as around Britain and in the West End. Her last live performance was at Windsor Castle for the Queen's Waterloo Dinner in 1973.
