In 1997 the series Stargate SG-1 first aired on American cable television and over the course of nearly nine seasons has developed its own unique mythological superstructure. Stargate SG-1 focuses on the dynamic relationships among the shows main characters, the four-person first-contact team: SG-1. Each week they are taken to new planets where ancient human civilizations have been seeded as slave populations by the shows arch-villains, the parasitic, body-snatching Goa'uld. The series' concerns therefore range from ancient cultures and contemporary politics, to aliens and advanced technologies, all given life with award-winning special effects and anchored by the central icon of the Stargate.