(written from a Production point of view)
Roger R. Cross (born 19 October 1966; age 49) is the Canadian actor who played Tret in the Star Trek: Enterprise episode "Extinction". He is perhaps best known for his role as CTU Agent Curtis Manning on the action drama television 24.
Although he was born in Christiana, Jamaica, Cross moved to Burnaby, British Columbia, Canada when he was eleven. He graduated from Trinity Western University in Langley, British Columbia, with a degree in Aviation and General Studies.
While waiting for work as a pilot in 1990, Cross took on jobs as a stuntman and background extra on films. and studied acting at the Breck Academy in Vancouver. He decided to focus on an acting career following his experience on his first film, entitled The International Rescue. 
Cross made his first television appearance on a 1990 episode of the CBS drama series Wiseguy, on which DS9 guest actor Jonathan Banks was a regular. This was followed by an episode of Neon Rider in 1992 with Antoinette Bower. His first made-for-TV movie was NBC's 1993 drama Miracle on Interstate 880, which was directed by Robert Iscove and which also featured Len Cariou and John Pyper-Ferguson. Cross was then seen in the CBS TV movie Judgment Day: The John List Story, which aired one day later; this project starred Alice Krige.
Between 1993 and 1994, Cross played the recurring role of Officer Terry Cooper on the crime drama series The Commish. Fellow Enterprise guest star Kaj-Erik Eriksen was a regular on this series. Cross and Eriksen later worked together in the 1996 TV adaptation of Captains Courageous and in a 2005 episode of The 4400 (along with Jeffrey Combs).
In 1994, Cross appeared in two TV movies starring Malcolm McDowell: Seasons of the Heart and The Man Who Wouldn't Die. That same year, he appeared in the second episode of the science fiction series M.A.N.T.I.S. along with Gregg Henry. In 1995, he co-starred in the pilot episode for another hit science fiction series, Sliders, which starred John Rhys-Davies.
Cross appeared in four episodes of The X-Files, including three directed by Rob Bowman and one directed by Kim Manners, as well as appearing with actors Jerry Hardin, Daniel Benzali, and Kevin Conway. Cross has also appeared on such science fiction shows as The Outer Limits (including an episode with John Savage and another with Marina Sirtis), Millennium (with Megan Gallagher and Bill Smitrovich), Stargate SG-1 Gene Roddenberry's Andromeda, Taken (with Matt Frewer), JAG (with Zoe McLellan and Adam Grimes), and the new Bionic Woman (starring Miguel Ferrer).
Cross portrayed Thurgood Marshall in the 1999 TV movie The Color of Courage, which also featured David Andrews and Bruce Greenwood. That same year, Cross appeared in the CBS movie Aftershock: Earthquake in New York, along with Sharon Lawrence, Mitchell Ryan, and Mark Rolston. His later TV movies include 2001's Sole Survivor (with Glenn Morshower) and 2002's Interceptor Force 2.
First Wave and 24
Cross was a regular on the series First Wave, which aired on the Sci-Fi Channel from 1998 through 2001. On this series, Cross portrayed "Joshua," an alien who assists Humans in preventing his race's invasion of Earth. One Cross' co-stars on First Wave was Rob LaBelle, who guest-starred on three episodes of Star Trek: Voyager.
Cross played CTU (Counter Terrorist Unit) Agent Curtis Manning on the hit FOX series 24 for 45 episodes between 2005 and 2007. Added at the start of the fourth season as a recurring character, Cross' character proved popular enough that he was promoted to series regular status midway through the season. Throughout much of the series, his character was a partner and friend of the lead protagonist, Jack Bauer (played by Kiefer Sutherland). Cross' character was killed off by Bauer in the show's sixth season when he threatened to kill a reformed terrorist played by DS9's Alexander Siddig. Cross worked with many other Star Trek alumni during his time on 24, including Jude Ciccolella, Jonathan del Arco, Megan Gallagher, Gregory Itzin, Tim Kelleher, Jeff Kober, Tzi Ma, Glenn Morshower, Tony Plana, Albie Selznick, Raphael Sbarge, Bill Smitrovich, Keith Szarabajka, Faran Tahir, Ned Vaughn, Peter Weller, and Ray Wise.
Cross made his first mainstream film appearance as a pilot in the 1993 comedy Look Who's Talking Now, which starred Kirstie Alley. He subsequently appeared in such feature films as Dangerous Intentions (starring Corbin Bernsen), Free Willy 3: The Rescue (with Patrick Kilpatrick), and the Paramount Pictures thriller Double Jeopardy (starring Ashley Judd and Bruce Greenwood).
Cross co-starred with Star Trek Nemesis's Dina Meyer in the 2001 thriller Deadly Little Secrets. He then had a supporting role in the 2002 action thriller Ballistic: Ecks vs. Sever, along with Gregg Henry. He also had a small role as a secret service agent in the second X-Men film, X2, which starred Patrick Stewart, Famke Janssen, and Bruce Davison.
More recently, Cross played the supporting role of Toail in the 2004 sci-fi action film The Chronicles of Riddick, which also starred Karl Urban. Cross then appeared in the 2005 comedy King's Ransom and the 2006 drama World Trade Center; other Star Trek performers who appeared in the latter included Jude Ciccolella, Brad William Henke, and Donna Murphy.
Cross' most recent film was the 2008 comedy Mad Money, with Christopher McDonald. His upcoming projects include the remake of the classic science fiction film The Day the Earth Stood Still.