(written from a Production point of view)
Born as Gregory Cameron Thor in Los Angeles, California, USA, Thor and fellow actress Alice Carter founded the Carter Thor Studio, an acting studio in the early 1990s. From these days on he coached many Hollywood actors including Sylvester Stallone, Cameron Diaz, Faye Dunaway, Sharon Stone, Gwen Stefani, and Madonna. 
Prior to his appearance on Star Trek, Thor guest-starred in a 1988 episode of the acclaimed television drama China Beach, starring fellow Star Trek alumni Robert Picardo, Megan Gallagher, Jeff Kober, and Concetta Tomei. This was followed in 1992 with an appearance on Cheers, starring Kirstie Alley, Kelsey Grammer, and Bebe Neuwirth. His other television credits include the television movies Johnny Ryan (1990, co-starring Clancy Brown and Paul Rossilli) and The Killing Mind (1991, with Tim DeZarn, Stan Ivar, Frank Novak, and Daniel Roebuck), and appearances on such series as Matlock, Mad About You, and seaQuest DSV.
Thor made his film debut in the 1986 comedy Modern Girls, starring Virginia Madsen, Clayton Rohner and Mark Holton. This was followed with roles in a number of popular films, including 1988's Punchline (with Mike Starr and George D. Wallace), 1991's Curly Sue (with Barbara Tarbuck), 1992's A Few Good Men (with David Bowe), 1993's Jurassic Park (with the voice of Richard Kiley), 1994's Clear and Present Danger (with Vaughn Armstrong, Reg E. Cathey, Raymond Cruz, Elizabeth Dennehy, Ellen Geer, and Harris Yulin), and 2002's Windtalkers (with Holmes Osborne and Christian Slater). He more recently appeared in 2005's Undiscovered, which also featured Peter Weller.