Season 5

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06.29.01 Enemies
 The SG-1 team, in their stolen Goa'uld mothership, has arrived in another galaxy, 125 years travel from Earth. Shortly after their arrival, Apophis' mothership arrives, carrying Teal'c, who had been shot with a staff weapon, and is presumed dead. As Apophis begins to attack, an unknown third ship arrives. (Part 2 of 2)
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07.06.01 Threshold
 His mind altered by Apophis, Teal'c must undergo an ancient ritual that takes him to the edge of death itself, in order for him to rediscover who he is. With assistance from Bra'tac, Teal'c is forced to relive several episodes from his life, from when he was still loyal to Apophis, while O'Neill, Carter, and Jackson sit by his side.
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07.13.01 Ascension
 After arriving on an alien planet for a routine survey mission, Samantha Carter passes out for no apparent reason. After returning to Earth, she takes some time away from the SGC, and unexpectedly finds herself in the company of a strange new friend. Guest starring Sean Patrick Flanery and John de Lancie.
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07.20.01 The Fifth Man
 Colonel O'Neill and Lieutenant Tyler are ambushed by Goa'uld forces and trapped behind enemy lines, fighting a new Jaffa faction under an unknown System Lord. Meanwhile, the rest of SG-1 discover that they don't know who Lieutenant Tyler is. Guest starring Dion Johnstone and John de Lancie.
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07.27.01 Red Sky
 SG-1 visits a new world populated by people who very much resemble the Amish in their way of life. Unfortunately, activation of the Stargate causes a variation in the sun's radiation. Thus, all life on the planet will soon die. The Asgard, who are the protectors of this world, are absent again for some unknown reason.
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08.03.01 The Rite of Passage
 Cassandra, who has been under the supervision and care of Dr. Fraiser, begins to have attacks of uncontrollable telekinesis, and her health deteriorates rapidly. Because of this problem, the SG-1 team travels back to her home world, to try and find something that can help her.
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08.10.01 Beast of Burden
 The Unas (last seen in Season 4's The First Ones) have been made slaves by a group of humans, and SG-1 is put in the position of having to decide if they are morally obligated to liberate the Unas from bondage. Daniel gets very personally involved, and at the end of the day the seeds of civil war are sown.
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08.17.01 The Tomb
 SG-1 must reluctantly team up with a Russian unit, on an off-world mission to investigate the disappearance of a rogue Russian Stargate team led by Major Valentine Kirensky. Dr. Jackson attempts to open the doorway and gain access to the inside of a Ziggurat structure, which is believed to be 3000 years old.
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08.24.01 Between Two Fires
 The fate of Tollana hangs in the balance as the SG-1 team strives to solve a mystery on the Tollan home world. Colonel Jack O'Neill tries to discover the motive behind the Tollans' sudden decision to share weapons technology with SG-1, contrary to their behavior in the past.
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08.31.01 2001
 SG-1 encounters a new world and a potential new ally in the war against the Goa'uld, though they do not yet know the Aschen's dark secret. SG-1 finds out that these people might very well be the ones that the future O'Neill may have been warning them about. (The Aschen were first seen in season 4's 2010.)
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09.07.01 Desperate Measures
 When Major Samantha Carter is abducted by a mysterious man in black, General Hammond authorizes Colonel Jack O'Neill and Daniel Jackson to go out and find her. The two men track Major Carter to a hospital where dangerous experiments are being conducted. Guest starring John de Lancie.
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09.08.01 Wormhole X-treme!
 Martin Lloyd (last seen in season 4's Point of No Return) pitches a script to a television studio, which reads suspiciously like the Stargate scenario. Colonel Jack O'Neill is sent to confront him. Stargate SG-1's entire team of writers and producers worked together to pen this special 100th episode.
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03.08.02 Proving Ground
 While training Air Force cadets at a top-secret facility, O'Neill learns of a possible alien incursion at the SGC. Knowing that other SG teams may be compromised, he has no choice but to take his young troops into a very real and very dangerous battle situation.
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03.15.02 48 Hours
 As the SG-1 team travels to Earth through the stargate, Teal'c is lost in transit, failing to materialize at Earth's gate. Carter tries to figure out a way to bring him back safely. Meanwhile, Daniel negotiates with the Russians for their help, and O'Neill uses his own sources to try and find the answer.
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03.22.02 Summit
 The Tok'ra learn that the Goa'uld System Lords are negotiating an alliance, and request Daniel Jackson's help to infiltrate the meeting. Meanwhile, the other members of SG-1 help the Tok'ra to evacuate their base, and Samantha Carter makes a surprising discovery. (Part 1 of 2)
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03.29.02 Last Stand
 With time running out to complete his plans, Daniel Jackson is confronted by Osiris before he is able to release the biological weapon supplied by the Tok'ra. At the same time, an attack force led by a mysterious Goa'uld approaches the Tok'ra home planet. (Part 2 of 2)
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04.05.02 Fail Safe
Earth finds itself threatened by something even larger than the Gou'ald, when the team learns that an asteroid is on a collision course with the planet. With no luck getting help from the Tok'ra or Asgard, the team must put together a plan to solve the problem on their own. (Note: This episode aired before Summit in the UK.)
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04.12.02 The Warrior
A charismatic Jaffa leader tries to rally his people against the Goa'uld, and seeks to forge an alliance with Earth. The SG-1 team travels to the planet with weapons and supplies, but encounters some resistance from both the people on the planet and from within their own ranks.
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04.26.02 Menace
SG-1 discovers a world that seems to have been destroyed by Replicators, where they find a young girl who may hold the secret to the salvation of the Asgard. After returning to the SGC, they make a very surprising discovery which has the potential to save them or kill them. Things quickly get out of hand.
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05.03.02 The Sentinel
After another SG team runs into trouble on a mission, the SG-1 team sends a UAV to the planet to investigate, and learns the Goa'uld have arrived there. O'Neill must turn to a pair of convicted criminals for help repairing an alien device, in order to save the world from annihilation by the Goa'uld.
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05.03.02 Meridian
An alien civilization is threatened with extinction when they attempt to build a weapon of mass destruction, exposing Daniel Jackson to a massive dose of radiation in the process. When SG-1 goes to the planet to investigate, one of the scientists from the planet comes forward with some disturbing information.
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05.17.01 Revelations
The SGC is contacted by the Asgard, who inform them that Thor has been killed by the Goa'uld, and they need help to rescue a stranded Asgard scientist. When the team arrives on the planet, they soon discover that Thor is alive, but he has been captured by Osiris and she is about to discover the secret Asgard laboratory.