<P> Stargate SG - 1 is a Canadian - American military science fiction television series created by Brad Wright and Jonathan Glassner . The series resumes the story of the 1994 Stargate film, where a military team led by Colonel Jack O'Neill and supported by the archeologist Daniel Jackson use an ancient alien artifact called the Stargate to travel to a planet where an alien named Ra oppressed the planet's people by posing as a god . After the Earth team defeated Ra, O'Neil returns to Earth while Daniel Jackson stays on the planet . The series pilot, which takes place roughly one year after the events of the film, reveals that Ra was not the only alien to use Stargates to transport human slaves to many worlds for thousands of years . </P> <P> Stargate SG - 1 premiered on July 27, 1997 on the subscription channel Showtime . After five seasons on the same network, the Sci Fi Channel bought Stargate SG - 1 and would air it for five further seasons, totalling to 214 episodes in ten seasons (seasons 1 through 7 consisted of 22 episodes each, and seasons 8 through 10 had 20 episodes each). Since the American broadcast splits each season to allow the production to catch up, the British channel Sky One aired the second part of some seasons before their American counterpart . Stargate SG - 1's finale episode premiered in the United Kingdom on Sky One on March 13, 2007 . The Sci Fi Channel concluded the tenth season on June 22, 2007 . All seasons of Stargate SG - 1 are available on DVD, and two direct - to - DVD Stargate films have continued the series, the first released in March 2008, the second in July 2008 . </P> <P> The cast of the first five seasons consisted of Richard Dean Anderson starring as Col. Jack O'Neill, Michael Shanks as Dr. Daniel Jackson, Amanda Tapping as Cpt. / Maj . Samantha Carter (who would be promoted to Lieutenant - Colonel in Season 8 and to Colonel in the films), Christopher Judge as the Jaffa alien Teal'c, and Don S. Davis as Maj. Gen. George Hammond . Michael Shanks left the series after Season 5, and his function was assumed by Corin Nemec as the non-earth human Jonas Quinn in Season 6 . Shanks continued to have a recurring role in season 6, rejoined the cast in Season 7, and stayed part of the main cast until the series' end . After Don S. Davis' departure from Stargate SG - 1 after Season 7, Richard Dean Anderson's character was promoted to Brigadier General in Season 8; Anderson left the series' main cast after that season, but continued to appear periodically . Ben Browder and Beau Bridges replaced them as Lt. Col. Cameron Mitchell and Maj. Gen. Hank Landry in Season 9, respectively . The last actor to join the main cast was Claudia Black, who resumed her previously recurring role as Vala Mal Doran in Season 9 . </P>

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