Frank Windsor Higgins (12 July 1928 – 30 September 2020), known professionally as Frank Windsor, was an English actor, primarily known for his roles on television, especially policeman John Watt in Z-Cars and its spin-offs.

Windsor attended Queen Mary's Grammar School, Walsall, and studied speech training and drama at the Central School of Speech and Drama, then based at the Royal Albert Hall, London.^[2] He played Detective Sergeant John Watt in Z-Cars from 1962 to 1965, and thereafter its spin-offs Softly, Softly (1966–1969), Softly, Softly: Task Force (1969–1976), Jack the Ripper (1973), and Second Verdict (1976). He also returned as Watt for the final episode of Z-Cars itself in 1978.

He appeared as "Tobin" in Series 6, Episode 9 of The Avengers.

In 1969, he appeared in the pilot episode of Randall and Hopkirk (Deceased) in the episode "My Late Lamented Friend and Partner" as Sorrensen, a wealthy businessman with a murderous streak. His lighter side was demonstrated in the pilot episode of the situation comedy The Dustbinmen in 1968, and as Scoutfinder General in an episode of The Goodies.^[3]

From 1987 to 1989, he starred in the comedy drama Flying Lady written by Brian Finch.^[4] He also starred as a rather old-fashioned headmaster grappling with problems in education in Headmaster, which started as a single play in Play for Today in 1974. It was expanded into a six-part series in 1977.

He had regular roles in the BBC drama Casualty; the ITV drama Peak Practice; he played Major Charlie Grace in EastEnders (1992); appeared twice in Doctor Who; had various stage roles, and in his later years appeared in television commercials advertising life-assurance policies for people over 50.^[3] He was the subject of This Is Your Life on 3 December 1975 when he was surprised by Eamonn Andrews at the Metropolitan Police Sports Club in East Molesey.^{[citation needed]}

He was married to Mary Corbett from October 1959 until his death. They had two children. Windsor died at his home in London in September 2020, at the age of 92.^[5][6]