La Tourneaux made his Broadway theatre debut in the 1967 musical Illya Darling . In 1968, he was part of the ensemble for Mart Crowley's play The Boys in the Band , which opened on April 14, 1968 at Theater Four in New York City.
La Tourneaux's career stalled after the film version of The Boys in the Band was released. His only other film performances were a supporting part in the Roger Corman film Von Richthofen and Brown (1971) and the independent film Pilgrimage . He also had a small role in a 1974 made-for-television version of the Maxim Gorky play Enemies . On stage, La Tourneaux appeared in a small role in a Broadway revival of The Merchant of Venice .
The openly gay La Tourneaux initially blamed his being typecast as a gay hustler for his inability to receive worthwhile roles. Unable to secure work as an actor La Tourneaux began nude modeling in gay men's magazines and in 1978 performed nude in a one-man cabaret act at the Ramrod, a New York City theater showing gay pornography films. He eventually became a prostitute.
He also gave an interview to a gay magazine naming his famous married closeted bisexual lovers, alleging one of them to have been Academy award-winning actor Christopher Walken. He also accused Walken of having an affair with another married actor, Robert Wagner, on the night of actress Natalie Wood's (Wagner's wife) unexplained death. In 1983, La Tourneaux was arrested for assault after trying to extract money from a client and was incarcerated at the Rikers Island prison. While in prison, La Torneaux attempted suicide.
In the early 1980s, La Tourneaux contracted AIDS, and received news coverage when he sought legal channels to prevent being evicted from his apartment when his landlord objected to the presence of a live-in caregiver. La Tourneaux won the court case, but died in Metropolitan Hospital on June 3, 1986. Boys co-star Cliff Gorman and his wife cared for him during his illness until his death.