Colleen Thornton (born 30 May 1946; age 78) was the former actress who (together with her twin sister Maureen) appeared as the Barbara series androids in the Star Trek: The Original Series second season episode "I, Mudd". She filmed her scenes on Wednesday 16 August 1967 at Desilu Stage 10.
Aside from her role on Star Trek, she also appeared with her sister as a "Hippie Twin" in film Coogan's Bluff (1968), with Seymour Cassel, Albert Henderson, Andy Epper, and Allen Pinson.
During the late 60s, the Thornton sisters became known as singers, and for a time, belonged to a troupe that performed the musical Hair: The American Tribal Love-Rock Musical. The sisters, identified as "The Gemini Twins" of Hollywood, were ejected from Acapulco, Mexico, in early January, 1969, for performing their production while only carrying a tourist visa. ('Mexican Authorities Cut Play Hair Short', Playground Daily News [Forth Walton Beach, FL], 9 January 1969, p. 20.)
In 1970, both sisters attended the Jimi Hendrix concert on Maui. Footage of both sisters at the concert later appeared on the 2020 Blu-Ray/DVD release of Live in Maui.
Thornton left acting and continued to work as a professional singer. By 1974, she was married to guitarist Richard Fortune, and was known for a time as Colleen Fortune. That year, the couple released the single "Boogie Man ". By 1978, they had started The Fortune Band, with Colleen and Maureen appearing on the debut album, Fortune (1978), as both singers, and on the album's cover. By end of 1982, Colleen left the band.