Alexander was born in London, the son of a doctor, and grew up in Yorkshire. He was educated at Ratcliffe College, Leicestershire, and Norwood College, Harrogate, and started acting in the theatre at the age of 16. During World War II he served in the British Army as a lieutenant with the 27th Lancers, and was seriously wounded when his armoured car was hit by artillery fire in Italy. In 1956, Alexander appeared on stage in Ring For Catty at the Lyric Theatre in London. He is probably best remembered as Charlie Hungerford from the detective series Bergerac, though he was also very prominent in the 1967 BBC adaptation of The Forsyte Saga. One of his early roles was in the children’s series Garry Halliday. He also appeared in one episode of Please Sir in 1970 as the headteacher of a rival school. Also in 1970, Alexander played Lord Uxbridge in Sergei Bondarchuk’s war epic Waterloo. Alexander appeared in many other film and television roles including three appearances in different roles in The Champions, The Avengers; Terry and June (1979–1980); Behind the Screen (1981–1982); the 1985 Doctor Who serial The Mark of the Rani; and The New Statesman (1987). On radio he starred as The Toff in the BBC radio adaptation of the John Creasey novels. He appeared in all but one episode of Bergerac from 1981 to 1991. He also played Commander Duffield in the 1985 pilot episode of Dempsey and Makepeace, Armed and Extremely Dangerous. He appeared on the West End in comedies and farces and his credits included Move Over Mrs Markham (1971), Two and Two Make Sex (1973), There Goes The Bride (1974–75) and Fringe Benefits (1976). At the time of Bergerac Alexander was blind in one eye due to a condition of the retina. He retired from acting in 1999, suffering from Parkinson’s disease. He lived in London with his second wife, the actress Jane Downs. He died on 28 May 2009.