[1] Barrett took the role of Malcolm Harris in Terry and June after the original actor Terence Alexander became unavailable to return for production to begin on the Christmas special, for he had just begun playing Charlie Hungerford in Bergerac.
He played Mr Campbell-Lewiston in The Fall and Rise of Reginald Perrin, episode 4 "The Bizarre Dinner Party".
Four years after leaving Terry and June, Barrett returned, this time playing a different character called Mr Basingstoke in the episode of the final series titled "They Also Serve".
He also appeared in episodes of Are You Being Served?, Dad's Army, Love Thy Neighbour, The Prince of Denmark, To the Manor Born and George and Mildred.
Although best remembered for his TV work, Barrett also appeared in films, including The Psychopath (1966), Where the Bullets Fly (1966), The Deadly Bees (1966), The Mummy's Shroud (1967), White Cargo (1973), The Slipper and the Rose (1976) and Bloodbath at the House of Death (1983).