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- You may also be looking for William O. Campbell.
William Campbell (30 October 1923 – 28 April 2011; age 87) , from Newark, New Jersey, was the actor known to Star Trek fans for his portrayal of the god-child Trelane in the first season episode "The Squire of Gothos" and for his role as Koloth in the the second season episode "The Trouble with Tribbles". He reprised the Koloth role in the Star Trek: Deep Space Nine episode "Blood Oath", becoming one of the few actors to portray the same character on both the original series and on one of the spin-offs. (The character Koloth also appeared in a Star Trek: The Animated Series episode, but in that case, James Doohan provided the voice.) Campbell also reprised his role as Trelane in the video game Star Trek: Judgment Rites. His Klingon teeth from "Blood Oath" were once sold off by auction. 
Campbell worked steadily in films and on television through the 1950s and 60s, beginning with the 1950 film noir The Breaking Point. In this film, Campbell appeared with fellow TOS guest performers Sherry Jackson and Peter Brocco. This was followed with supporting roles in an extensive number of movies, including Operation Pacific (1951), Battle Circus (1953), Escape from Fort Bravo (1953), The High and the Mighty (1954, co-starring Paul Fix and William Schallert), Battle Cry (1955, with Perry Lopez), and Man Without a Star (1955, with George D. Wallace).
Although Campbell received acclaim for his first starring role as a prisoner awaiting execution in the 1955 crime drama Cell 2455 Death Row, it did little to advance his career and returned to doing supporting roles. As one of the principal actors in 1956's Love Me Tender, Campbell became the first actor to sing with Elvis Presley in a film. Campbell then performed in such films Eighteen and Anxious (1957, with Yvonne Craig), and The Naked and the Dead (1958, also featuring Grace Lee Whitney). Campbell became a regular on the Canadian TV series Cannonball, which lasted 39 episodes between October 1958 and July 1959.
By the 1960s, he began to appear more prominently on television, although he continued acting in low-grade films. In 1963, he was given the lead role in Francis Ford Coppola's 1963 cult horror movie Dementia 13, having worked with Coppola on Roger Corman's The Young Racers the year before. In 1964, Campbell appeared in Corman's war drama The Secret Invasion and had a supporting role in the Academy Award-nominated classic Hush... Hush, Sweet Charlotte. Campbell also had an uncredited role in 1965's The Money Trap, starring Ricardo Montalban. In 1966, Campbell starred as a vampire artist who kills women and places their bodies within his sculptures in Roger Corman's Blood Bath, co-starring Biff Elliot and Sid Haig.
Campbell's television credits during this time included appearances on Philip Marlowe (in an episode with Barry Atwater), Perry Mason (including an episode with Kenneth Tobey), The Wild Wild West (in an episode with Maggie Thrett, written by Gene L. Coon), Combat!, Bonanza, and Gunsmoke (including one episode with James Gregory and Ed McCready, directed by Vincent McEveety). In addition, TOS director Herschel Daugherty cast and worked with Campbell in a 1968 episode of It Takes a Thief! with Meg Wyllie and a 1969 episode of Bracken's World.
In 1971, Campbell co-starred with TOS regular James Doohan in Pretty Maids All in a Row, a comedy written and produced by Trek creator Gene Roddenberry. Dawn Roddenberry also had a small role in the film. The following year, Campbell co-starred with Bernie Casey in the blaxploitation classic Black Gunn, which was Campbell's last feature film credit, although he continued to act on television. He appeared with his TOS co-star George Takei and "Trouble with Tribbles" co-star Stanley Adams in a 1971 episode of the short-lived drama O'Hara, U.S. Treasury, written by Gilbert Ralston. This was followed with appearances on Ironside (with Antoinette Bower), Emergency! (with Vince Howard, Ken Lynch, and Kevin Tighe, directed by Joseph Pevney), Adam-12 (with Vic Perrin), The Manhunter (with William Smithers), another episode of Gunsmoke, Marcus Welby, M.D., Medical Center (with Barbara Baldavin and Louise Sorel, directed by Joseph Pevney), The Streets of San Francisco (with Darleen Carr, Jason Evers, and Ken Lynch), and The Hardy Boys/Nancy Drew Mysteries (with William Schallert, and directed by Michael Pataki).
In 1983, Campbell appeared in a two-part episode of Quincy, M.E., which featured Robert Ito and Garry Walberg as regulars, and was co-written and directed by Jeri Taylor. In 1985, he co-starred with Barbara Babcock and Richard Kiley in an episode of Hotel. In 1987, he co-starred with Gary Lockwood in the TV special The Return of the Six Million Dollar Man and the Bionic Woman.
Campbell's work in the 1994 DS9 episode "Blood Oath" and a 1996 appearance in an episode of Kung Fu: The Legend Continues were his final two acting roles. He described his role on "Blood Oath" as his most difficult acting job, and one he would have liked to do again. Though he very rarely made public appearances, Campbell appeared at the Star Trek 40th anniversary convention in Las Vegas in August 2006.
- "William Campbell", Star Trek: The Magazine Volume 1, Issue 13, May 2000, pp. 48-53