He also appeared in Taxi!, Dixon of Dock Green, The Power Game, The Avengers, Softly Softly , Z Cars, Doomwatch , Rooms, Death of an Expert Witness, Rumpole of the Bailey and Two Thousand Acres of Sky.
Brooks has been in several significant television productions: in 1966 he was the male lead in Cathy Come Home, a seminal television play which has been voted one of the best productions ever by the BFI. A few years later he endeared himself to a generation of children when he narrated the animated series Mr Benn. In the 1980s and 1990s he starred in two popular dramas - Big Deal and Growing Pains and then spent two years in EastEnders as the murderous Joe Macer.
In film, he had a big success in the 1960s with The Knack …and How to Get It but also appeared in Damn the Defiant! and Daleks: Invasion Earth 2150 A.D.