The series debuted on Showtime on July 27, 1997, and moved to the Sci-Fi Channel after its fifth season. It starred Richard Dean Anderson (as O'Neill) and Michael Shanks (as Jackson), alongside Amanda Tapping, Christopher Judge and Don S. Davis respectively playing the new characters Samantha Carter, Teal'c and George Hammond. The cast remained fairly regular for most of "SG-1"'s run, but experienced some changes. Michael Shanks left the show at the end of Season 5 and was replaced by Corin Nemec as Jonas Quinn. Shanks returned at the beginning of Season 7 and Nemec was written out. At the end of Season 7 Davis left the show and Anderson filled the gap he left in the story. Season 9 saw the departure of Anderson, but added new regulars Beau Bridges and Ben Browder. After a debut episode in Season 8, followed by appearances in eight episodes of Season 9, Claudia Black's popular reception earned her a position in the regular cast in Season 10.