SG-1 returns to Cimmeria, and finds that without protection from the Asgard the planet has been invaded by the Goa'uld.

The SG-1 team attempt to rescue Teal'c's son, who has been kidnapped and brainwashed by Apophis. Teal'c learns disturbing news about his wife.

SG-1 discovers a military camp where young men are trained to impersonate SGC personnel to infiltrate Earth.

SG-1 encounters an entire planet suffering from amnesia. The planet's leader returns to Earth with SG-1 to find a cure, but SG-1 suspects she may not be who she appears to be.

SG-1 investigates a conspiracy theorist who has detailed knowledge of the Stargate program.

The Tollan offer Earth advanced weapons technology, prompting a secret investigation on Tollana -- one that leads to a startling discovery.

When Carter goes missing, O'Neill teams up with Col. Maybourne again to free her.

Colonel O'Neill is trapped on an alien planet with Maybourne, and must fight to stay alive as his companion becomes increasingly paranoid.

General Hammond and the Pentagon reveal the existence of the Stargate to other world governments, and must defend the fact that the program is operated by the United States military.

SG-1 comes to the aid of a world about to be invaded by the Goa'uld, only to discover that the local king is Earth's Harry Maybourne.