Major Kawalsky is possessed by a Goa'uld, and the SGC must find a way to remove it without killing him.

An alien artifact transports Daniel to an alternate reality, where he is not a part of the Stargate program and the Goa'uld -- led by Teal'c -- are invading Earth.

A group of primitive aliens begin to fall deathly ill after SG-1 arrives.

Members of SG-1 become infected with an alien virus that turns them into primitive beings. Dr. Fraiser must find a cure to save the team and the alien population from whom it was contracted.

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.

Earth provides sanctuary for Vala's estranged, con artist father after he provides intel about a Jaffa plot to attack the planet.

SG-1 finds a medieval Christian society terrorized by Sokar and the Unas, and is accused of being possessed by demons.

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

The impending wedding of his son is the least of Teal'c's worries when the Hak'tyl plan an uprising against the Goa'uld Moloc, driving a wedge between Teal'c and Ishta.

SG-1 is imprisoned in a virtual reality realm and forced to relive the worst moments of their lives over and over.

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.

Teal'c is infected with deadly venom from a giant insect, and begins a terrible transformation. When he escapes the S.G.C., SG-1 must find him before Colonel Maybourne does.

The SGC is invaded by an alien life force that takes up residence in the base computer system -- and in Major Carter.

Cassandra mysteriously falls ill, sending SG-1 back to her home planet -- where they uncover a dark Goa'uld secret.

SG-1 investigates a secret N.I.D. laboratory, where a ruthless scientist has used cloning technology to create a Goa'uld-human hybrid.

Jackson becomes addicted to the effects of a Goa'uld sarcophagus, and falls for the planet's manipulative princess.

SG-1 finds a planet inhabited by Native American Indians, protected by spirits who are actually advanced alien shapeshifters.

SG-1 finds a deserted Goa'uld palace, where a beautiful device causes suicidal tendencies.

The team returns to Earth with a piece of technology that allows them to see alien creatures everywhere, and must attempt to contain the problem when it spreads beyond the base.

The team finds a fugitive colony of Jaffa women, who must prey on other Jaffa to acquire symbiotes.

The newly-elected president is debriefed about the Stargate program, and Vice President Kinsey makes a new play for control of the program.

A tour of an off-world research base for a group of foreign diplomats turns dangerous when an insidious insect species gets loose.

Teal'c discovers a world where people are being savagely attacked by an elusive creature, leading SG-1 to a stunning discovery about its potential origin.

An alien civilization is forced to reconsider their views on women when Carter rebels against their social customs.

SG-1 discovers an elderly man known for developing technology to fight the Goa'uld. Daniel is tricked into switching bodies with the man, Ma'chello, who believes he is "owed" for all the good he has done.