Season seven of Stargate SG-1 began airing on June 13, 2003 on the US-American Sci-Fi Channel. The seventh season concluded after 22 episodes on March 19, 2004 on British Sky One, which overtook the Sci-Fi Channel in mid-season. It was intended on being SG-1's final season, where Stargate: Atlantis would continue on.
Jonas Quinn is captured by Anubis, where he learns of the location of Langara, and the Naquadria so he can use the element to rebuild his superweapon. While Anubis holds the planet prisoner, Teal'c is having a hard time convincing Yu's forces to attack Anubis, so he has his First Prime, Oshu convince Ba'al to join in.
A teenager claiming to be ColonelJack O'Neill arrives in Stargate Command. Believing him to be an imposter, the teen manages to recite every key event from fellow team members. After believing it to be O'Neill, they find out he's a botched clone. They investigate what has happened to the real O'Neill.
Teal'c is shot on a mission and is determined to make his recovery as quick as possible, since Rya'c and Bra'tac have been captured and work as slaves on Erebus. Dr.Daniel Jackson starts to remember a few events from his time while he ascended, and uses them to aid several SG teams to infiltrate the labor camp and rescue the imprisoned Jaffa.
SG-1 finds a civilization living in a Dome on an unlivable planet. The seemingly peaceful civilization use geothermal energy to maintain the dome. However, mysteriously, several people start disappearing, and the dome is slowly shrinking.
While examining a crashed alien ship called the Stromos, Dr.Daniel Jackson is struck with a power surge. After returning to Stargate Command, it is discovered that several consciousnesses from the people trapped in stasis are in Jackson's head.
SG-11 is attempting to mine Naquadah on P3X-403 and have alerted a number of native Unas, after they provoked their sacred ground. The only hope for a truce is for Dr.Daniel Jackson to bring Chaka to 403. However, the Tau'ri military do not wish an alliance.
After his job is threatened, Dr.Jay Felger desperately plans on Avenger, a computer virus that could render a Dial Home Device useless to keep his position in Stargate Command. However, the plan goes awry, as soon, every Stargate in the Milky Way is affected, caused by the virus, which puts the entire galaxy into a stand still.
SG-1 encounter the Hak'tyl Resistance, a group of rebel Jaffa females who renounced their "god" Moloc as a false one, after realizing he had ordered all young females to be put to death. SG-1 propose that they no longer need to rely on symbiotes, since they are running low on them, and offers them a substitute, Tretonin. Meanwhile, Teal'c gets closer to the Hak'tyl leader, Ishta.
Anubis has created an army of invulnerable killing machines called Kull warriors to do his work and wipe out the rival Goa'uld. They have armor that impervious to all known weapons. The only way to stop them is for Dr.Daniel Jackson to go to a hidden temple in Honduras that is the origin of the "fountain of youth" myth.
Dr.Daniel Jackson and Dr.Bill Lee are captured by Honduran rebels after getting their hands on a device that could stop the Kull warriors. As ColonelJack O'Neill launches a secret mission with an old acquaintance to retrieve the two, the rest of the team uncover more information on the warriors by infiltrating Tartarus, the planet on which they are created.
While on a routine journey to Earth, the Prometheus makes first contact with an unfriendly ship, and is attacked. Whilst retreating to a Interstellar cloud, MajorSamantha Carter is knocked unconscious. She awakens only to find the ship completely abandoned in the Interstellar cloud, but has several hallucinations of the rest of team, and a little girl named Grace.
Dr.Daniel Jackson is plagued with several dreams involving his past, but this time is pushed by Sarah Gardner to reveal the location of the Lost City. However, little does he know, Osiris visits him in his sleep every night until he can find out the city's location. Meanwhile, MajorSamantha Carter is seeing someone, a Denver cop named Pete Shanahan.
The Kull warriors have infiltrated the alpha Site, where work on a weapon to stop them is taking place. The base is destroyed, but MajorSamantha Carter is missing, on the run, trying to hide from a warrior. Meanwhile, the Tok'ra-Tau'ri-Jaffa alliance is once again challenged.
Towards the end of his term, the President of the United States sends a film crew to document the life of SGC personnel in case the public gets news of the Stargate Program's existence.
SG-1 minus ColonelJack O'Neill are in Los Angeles where the NID discover a rogue experiment. Also, a Goa'uld explosive device is activated, and they have only hours to deactivate it, or the entire city will be destroyed.
Anubis is sending his entire fleet to Earth to gather the whereabouts of the Lost City. Meanwhile, ColonelJack O'Neill, who is starting to get affected by the Ancient knowledge, leads SG-1 to Proclarush, which is believed to be the location of the Lost City, only to find that they have to return to Earth, which is the location of the city, Atlantis.
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