In 1959, Brooks starred in Saul Levitt’s hit play The Andersonville Trial with Brian Donlevy and Charles Durning. He was very proud of his theatre work that included An Enemy of the People and I Am a Camera, as well as the actors with whom he appeared, including Julie Harris and Barbara Bel Geddes. Brooks was also in John Steinbeck's Burning Bright as Victor with Kent Smith as Joe Saul, Barbara Bel Geddes as Mordeen, and Howard Da Silva as Friend Ed which he had adapted from his 1950 novel of the same name.
Television
In the 1950s, Brooks appeared in The Philco–Goodyear Television Playhouse.In the 1960s, he appeared in Combat!. In the 1972–73 TV season, he had a recurring role as Deputy D.A. Chapman in McMillan & Wife. In the fall of 1977, Brooks and Richard Anderson became the first known actors to portray the same characters as regulars simultaneously on two different networks. NBC picked up The Bionic Woman after the series had been cancelled by ABC. ABC continued to air The Six Million Dollar Man. Brooks had, by that time, been promoted to series regular on both series. The unusual situation lasted only one season as the two series were cancelled by their respective networks in the spring of 1978. Brooks reprised the role of Wells in three television movies: The Return of the Six-Million-Dollar Man and the Bionic Woman, Bionic Showdown: The Six Million Dollar Man and the Bionic Woman and Bionic Ever After?. His other television roles include in Mike Snow in Hunter, Dr. Arthur Bradshaw in General Hospital, Car 54, Where Are You?, Gunsmoke, , Night Gallery, Love, American Style, The Mod Squad, and Edgar Randolph in the soap opera Dallas, in a story arc involving J.R. Ewing. Brooks also guest-starred in an episode of The Silent Force in 1970. He appeared in Knots Landing as Ted Burton in the 1990s.
Writing
Brooks wrote two novels: Danny Brown and Roman Candle. His play Flo and Joe was optioned for a Broadway production and received several workshop productions at the Actors Studio and at Theatre West.
According to Jon Landau, Brooks was the "soulmate" of Landau's mother, Edie, for over 20 years. They were friends as children and reconnected in 1993 after her husband died. Brooks was friends with Charles Durning when they met in 1959 in Saul Levitt’s hit play The Andersonville Trial until Durning's death in 2012. Brooks died on December 7, 2015, of natural causes at his home in Studio City, Los Angeles, one week after reaching age 90.
