Star Trek
In various roles, Barrett participated in every incarnation of the popular science fiction Star Trek franchise produced during her lifetime, including live-action and animated versions, television and cinema, and nearly all of the time periods in which the various series have been set.
She first appeared in Star Trek's initial pilot, "The Cage" (1964), as the USS Enterprise's unnamed first officer, "Number One". Barrett was romantically involved with Roddenberry, whose marriage was on the verge of failing at the time, and the idea of having an otherwise unknown woman in a leading role just because she was the producer's girlfriend is said to have infuriated NBC network executives who insisted that Roddenberry recast the role. William Shatner corroborated this in Star Trek Memories, and added that female viewers at test screenings hated the character as well. Shatner said that female viewers felt she was "pushy" and "annoying" and also thought that "Number One shouldn't be trying so hard to fit in with the men." Barrett often joked that Roddenberry, given the choice between keeping Mr. Spock (whom the network also hated) or the woman character, "kept the Vulcan and married the woman, 'cause he didn't think Leonard [Nimoy] would have it the other way around".
When Roddenberry was casting for the second Star Trek pilot, "Where No Man Has Gone Before", she changed her last name from Hudec to Barrett and wore a blonde wig for the role of nurse Christine Chapel, a frequently recurring character, who was introduced in "The Naked Time", the sixth new episode recorded, and was known for her unrequited affection for the dispassionate Spock. Her first appearance as Chapel in film dailies prompted NBC executive Jerry Stanley to yodel "Well, well—look who's back!"
In an early scene in Star Trek: The Motion Picture, viewers are informed that she has now become Doctor Chapel, a role which she reprised briefly in Star Trek IV: The Voyage Home, as Commander Chapel. Barrett provided several voices for Star Trek: The Animated Series, including those of Nurse Chapel and a communications officer named M'Ress, an ailuroid officer who served alongside Uhura.
Barrett returned years later in Star Trek: The Next Generation, cast as the outrageously self-assertive, iconoclastic Betazoid ambassador, Lwaxana Troi, who appeared as a recurring character in the series, often visiting her daughter Deanna, the ship's counselor. Her character often vexed the captain of the Enterprise, Jean-Luc Picard, who spurned her amorous advances. She later appeared as Ambassador Troi in several episodes of Star Trek: Deep Space Nine, where her character developed a strong relationship with Constable Odo.
She was the regular voice of the onboard computers of Federation starships for Star Trek: The Original Series, Star Trek: The Next Generation, Star Trek: Deep Space Nine, Star Trek: Voyager, and most of the Star Trek movies. She reprised her role as a shipboard computer's voice in two episodes of the prequel series Star Trek: Enterprise, thus making her the only actor to have a role in all six televised Star Trek series produced up to that time. She also lent her voice to various computer games and software related to the franchise. The association of her voice with interactions with computers led to Google's Assistant project being initially codenamed Google Majel. She made a point of attending a major Star Trek convention each year in an effort to inspire fans and keep the franchise alive.
On December 9, 2008, shortly before her death, Roddenberry Productions announced that she would be providing the voice of the ship's computer again, this time for the 2009 motion picture reboot of Star Trek.
