Born in London into a theatrical family, and educated at the Nautical College Pangbourne, Cross started off by writing children's plays in the 1950s. He achieved instant success with his first play, One More River, which dealt with a mutiny in which a crew puts its first officer on trial for manslaughter. The play premiered in 1958 at the New Shakespeare Theatre Liverpool, starring Robert Shaw, directed by Sam Wanamaker, and in 1959, still with Robert Shaw, directed by Guy Hamilton at the Duke Of York's Theatre in London.
Cross' second play, Strip the Willow, was to make a star out of his Future wife, Dame Maggie Smith, even though the play was staged only in the provinces, never receiving a London production. In 1962, he translated Marc Camoletti's classic farce Boeing Boeing, which went on to have a lengthy and highly lucrative run in the West End. In 1964, he directed the play in Sydney. Another of his successes was Half a Sixpence, a musical comedy based on the H.G. Wells novel Kipps. This opened in 1963 and, like his first play, ran in London for more than a year.
He died in London in 1998, three weeks and three days before his 67th birthday. He was the stepfather of Maggie Smith's children from her earlier marriage, actors Toby Stephens and Chris Larkin.
