(written from a Production point of view)
Tricia O'Neil (born 11 March 1945; age 75) is an actress from Shreveport, Louisiana, who portrayed three Star Trek characters in the early 1990s. Perhaps her most notable role was that of Captain Rachel Garrett in the Star Trek: The Next Generation third season episode "Yesterday's Enterprise". She went on to make a second appearance on TNG as the Klingon scientist Kurak in the sixth season episode "Suspicions" and also appeared on Star Trek: Deep Space Nine as the Cardassian observer Korinas in the third season episode "Defiant". For Defiant, she filmed her scenes between Monday 3 October 1994 and Wednesday 5 October 1994 on Paramount Stage 4. Her makeup was applied by Camille Calvet and her costume was also worn by Elle Alexander in the DS9 seventh season episode "The Dogs of War" before it was sold off on the It's A Wrap! sale and auction on eBay.  She was also considered for the role of Kai Opaka that ultimately went to Camille Saviola. 
O'Neil began her career in show business as a model and magazine cover girl before she pursued acting, first in television commercials. Performing since the 1960s, she made her Broadway debut in the original musical Two by Two in 1970. For her performance as O'Neill in this production, O'Neil won a 1971 Theatre World Award. The following year, she appeared in her first motion picture, a blaxploitation western called The Legend of N*gger Charley, with Star Trek: The Original Series guest actor Fred Williamson portraying the title role. She was subsequently cast as a regular on the NBC soap opera How to Survive a Marriage, which ran from January 1974 through March 1975. Among her co-stars on this series was F. Murray Abraham, with whom she worked again in 1976 when she was a stand-by on the Broadway play Legend. O'Neil's second film was The Gumball Rally, the popular 1976 racing comedy starring Michael Sarrazin.
O'Neil's early television appearances include guest appearances on Ellery Queen (with Katherine Woodville), Delvecchio (with Anthony Caruso and James B. Sikking), and Barney Miller (with Ron Glass and James Gregory) and such made-for-TV movies as CBS's Mary Jane Harper Cried Last Night (1977, co-starring Phillip Richard Allen, Ray Buktenica, Bernie Casey, Charles Lucia, Warren Munson, and Nancy Parsons, with cinematography by Gayne Rescher) and Columbo: How to Dial a Murder (1978, with Ed Begley, Jr. and Kim Cattrall). Throughout the 1980s, she appeared on such shows as Hart to Hart (with Warren Munson and Bert Remsen), The Fall Guy (two episodes, including one with Marc Alaimo, Marshall R. Teague and Ian Wolfe), Hardcastle and McCormick (starring Brian Keith and Daniel Hugh Kelly), The A-Team (with Dwight Schultz, Sid Haig, Ed Lauter and Michael Ensign; one of her two episodes was directed by Mike Vejar), Scarecrow and Mrs. King (in an episode directed by Vincent McEveety and co-starring Eric Server), Murder, She Wrote (with Alice Krige and George Murdock), Dynasty (with Joan Collins, Warren Munson and Anthony Zerbe), MacGyver (with Richard Lineback), Simon & Simon (including an episode with Fionnula Flanagan), and L.A. Law (directed by Win Phelps and co-starring Corbin Bernsen, Michael Bofshever, Tim de Zarn, Larry Drake, Jennifer Hetrick, Marnie McPhail, and Randy Oglesby). She also appeared in an episode of The Powers of Matthew Star written by Walter Koenig.
Following her first appearance on The Next Generation, O'Neil's television credits included appearances on two episodes of Matlock (one with Jason Wingreen, the second with Daniel Roebuck), a Dallas two-parter (working alongside Mary Crosby, Joel Grey, and Richard Lineback), two episodes of Murder, She Wrote (one with Melvin Belli and another with Alan Oppenheimer), a Richard Compton-directed, David Gerrold-written episode of the science fiction series Babylon 5 (starring Andreas Katsulas), an episode of Diagnosis Murder with James Sloyan, two episodes of Beverly Hills, 90210 (including one with Vaughn Armstrong and Ann Gillespie), and two episodes of JAG (one episode with Thomas Kopache and another directed by James Whitmore, Jr. and starring Scott Lawrence). In addition, she had a supporting role as a judge in the 1991 comedy Ted and Venus, co-starring Andrea Martin, Vincent Schiavelli, and Brian Thompson. Ted and Venus was her first film since the James Cameron-directed Piranha Part Two: The Spawning in 1981, in which she played the lead. She again collaborated with Cameron in a small role in his 1997 Academy Award-winning blockbuster Titanic, co-starring Michael Ensign and David Warner and released by Paramount Pictures.
Other Trek connections
- Brave New World (1980 TV movie, with Jeanetta Arnette, Casey Biggs, and Julie Cobb)
- Jacqueline Susann's Valley of the Dolls (1981 TV movie, starring Catherine Hicks and featuring Janet MacLachlan and Byron Morrow)
- Voyagers! episode "Old Hickory and the Pirate" (1982, with Lance LeGault)
- The Murder of Sherlock Holmes (1984 TV movie, with Paddi Edwards, John Hancock, and Brian Keith; directed by Corey Allen)
- Kay O'Brien episode "Princess of the City" (1986, co-starring Keone Young; directed by Richard Colla)
- Hunter episode "Night on Bald Mountain" (1987, with Parley Baer)
- Baby M (1988 TV movie, with Dakin Matthews, Bruce McGill and Helene Udy)
- Police Story: Gladiator School (1988 TV movie, with Ray Buktenica; directed by James Darren)
- Gengis Khan (1992 film, co-starring Julia Nickson-Soul)
- Civil Wars episode "Whippet 'Til It Breaks" (1992, with Richard Riehle and Don Stark)
- A Woman Scorned: The Betty Broderick Story (1992 TV movie, co-starring Jeff Allin, Stephen Collins, Thomas Kopache, Brian Markinson, Stephen Root, and Susanna Thompson)
- Robin's Hoods episode #1.4 (1994, with Richard Herd)
- Degree of Guilt (1995 TV movie, with Sharon Lawrence)
- Babylon 5: In the Beginning (1998 TV movie, with Theodore Bikel, Andreas Katsulas, J. Patrick McCormack, and Robin Sachs; directed by Mike Vejar)
- Gia (1998 TV movie, with Alexander Enberg and Joan Pringle)