Season One
In order to counter the threat of the Goa'uld, the US government creates Stargate Command and series of SG-teams in order to explore the galaxy through the stargate and fight the threat of the Goa'uld and discover advanced technology for Earth.

Season Two
With an invasion of Earth closely avoided, SG-1 encounters the Goa'uld resistence as new and powerful Goa'uld enter the scene. Death stalks an old foe as the threat to Earth increases.

Season Three
With the threat of the Goa'uld bigger than ever, a non-aggression treaty is signed to save Earth. Sokar, an ancient an incredibly powerful Goa'uld has set his sights on galactic domination. A new enemy that even the might Asgard can't deal with surfaces.

Season Four
The Asgard face the Replicators as Earth fends off the mighty forces of Apophis thathave even the Goa'uld on edge. It is discovered that the SGC isn't the only place on Earth with a stargate.

Season Five
A new and powerful Goa'uld surfaces, threatening both Earth and the System Lords with his power.The Tok'ra take a fall and in the end, a new path will present itself to a member of the team.

Season Six
The threat of Anubis becomes more serious, the Replicators take center stage as well as an ajustment to the loss of a team member. The existence of the stargate may be exposed to several other countries.

Season Seven
Daniel Jackson returns, and the quest for the secrets of the Ancients takes a more important role during the season.