The story of Stargate SG-1 begins about a year after the events of the feature film, when the United States government learns that an ancient alien device called the Stargate can access a network of such devices on a multitude of planets. SG-1 is an elite Air Force special operations team, one of more than two dozen teams from Earth who explore the galaxy and defend against alien threats such as the Goa'uld, Replicators, and the Ori.
"When powerful aliens come through Earth's Stargate, Colonel Jack O'Neill returns to Abydos to retrieve Daniel Jackson, who has discovered that the alien transit system includes much more than the two planets."
"Colonel O'Neill, leading the new SG-1, track Apophis back to the planet Chulak to rescue Sha're and Skaara, and befriend one of Apophis' Jaffa guards."
"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."
"During an off-world assignment, Jack is struck down by energy from a blue crystal... which creates a duplicate of him that returns to Earth in Jack's place."
"Pressed by the government to acquire new technologies, SG-1 is led to a world inhabited by a seemingly primative race. When Apophis arrives, SG-1 ambush him with disasterous consequences."
"SG-1 discovers a race of attractive people who age extremely rapidly. The situation becomes personal when O'Neill begins to suffer from the same accelerated aging, and must live out the rest of his life on the planet."
"SG-1 tracks down Catherine Langford's fiancee, who took the first Stargate trip in 1945, and discovers an ancient meeting hall that may hold the secrets of the universe itself."
"The banished Goa'uld Hathor is found in an ancient sarcophagus Earth, and takes over the S.G.C. with hopes of raising a new army against the System Lords."
"A mysterious affliction wipes out the entire population of a planet, plus an SG team -- except for one young girl. Carter befriends her, but learns that she is being used by the Goa'uld."
"Teal'c must stand trial for a crime committed while he served as first prime of Apophis when a villager on an alien world identifies him as the Jaffa who killed his father."
"The SG-1 team rescues a group of advanced humans from a planet near destruction, and must find a new home for the refugees before the Pentagon gets their hands on them."
"Colonel O'Neill and Captain Carter are separated from Jackson and Teal'c during a Stargate journey, and are trapped on a desolate ice world with no way of escape."
"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."
"Senator Kinsey arrives at the SGC to investigate the program and determine whether the great drain on the U.S. budget is worthwhile, prompting the team to recall missions from the past year."
"SG-1 escapes through the Stargate before it is shut down, and learns that Daniel's alternate reality vision is true: Apophis is moving to attack Earth from above. The team must stop Apophis and his son, Klorel, who inhabits the body of their friend Skaara."
"Jackson discovers that his wife has returned to Abydos, and is nine months pregnant with the son of Apophis. O'Neill must keep the secret of the Stargate program from being uncovered."
"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."
"SG-1 locates the Tok'ra, a Goa'uld resistance movement who oppose the System Lords, and attempt to form an alliance. Jacob Carter's cancer brings him near death."
"While SG-1 tries to form an alliance with the Tok'ra, a spy betrays the rebels to the Goa'uld. Jacob Carter finds that the Tok'ra may be his only hope of survival"
"SG-1 is accused of stealing an important weather-controlling device, sending a primative planet into chaos. The team discovers that Earth's second Stargate is being misused."
"After gating to a world on the edge of a black hole, the S.G.C. cannot disengage the Stargate. All of Earth becomes endangered by the time-distorting gravity field."
"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."
"A young boy arrives through the Stargate, and warns of plot by invisible aliens to kill all of the human race in order to rob the Goa'uld of potential hosts."
"O'Neill, Carter and Jackson must escape Hathor's clutches, while Teal'c tries to raise a Jaffa army on Chulak. General Hammond must take desperate measures to rescue the team."
"SG-1 must free an alternate reality Earth from a Goa'uld invasion after duplicates of Samantha Carter and Charles Kawalsky come through the quantum mirror."
"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 receives alien brain implants that manifest themselves as a bizarre man, who tells them that they would not survive the procedure to remove him."
"SG-1 faces creatures of mass destruction that even the Asgard can't control, and must destroy Thor's infested vessel before the Replicator bugs reach Earth."
"O'Neill and Teal'c risk their lives to keep the Replicator bugs from gaining a foothold on Earth, while Carter helps the Asgard fend off a Replicator invasion."
"When a member of the SGC tries to kill a Tok'ra, it is revealed that O'Neill and Carter may be victims of an untraceable form of Goa'uld mind control."
"Carter must help keep a promising young cadet from throwing away a future at the SGC. O'Neill and Teal'c encounter a dangerous life form at an offworld research base."
"SG-1 must rescue an alien world from the Goa'uld -- with help from an unexpected source. Teal'c seeks revenge on the System Lord Cronus for the murder of his father."
"SG-1 helps to evacuate the Tok'ra to a new base -- but matters are complicated when a spy reveals their location to Apophis. The team attempts a daring plan to take out the Goa'uld's powerful fleet."
"SG-1 finds themselves stranded in a crippled ship in a distant galaxy -- with Apophis threatening to destroy them. Teal'c is brainwashed and made loyal to Apophis once again."
"O'Neill and Lieutenant Tyler are ambushed by Goa'uld forces and trapped behind enemy lines -- while the rest of their team discover they don't know who Tyler is."
"An alien ship approaches Earth, sending SG-1 to an old friend for some answers -- where they discover that Martin Lloyd has created a TV show about the Stargate program."
"SG-1 trains a team of raw cadets, and Colonel O'Neill is forced to take them into a real-life battle situation when he learns of a possible alien incursion at the SGC."
"Dr. Jackson's undercover mission to a Goa'uld summit is complicated by the arrival of a surprise guest. The rest of the team face a full-scale invasion of the Tok'ra homeworld."
"Earth finds itself threatened by something even larger than the Goa'uld when the team learns that an asteroid is on a collision course with the planet."
"Tragedy reunites Teal'c with his son, who blames him for the death of his mother. O'Neill and Carter launch a risky plan with untested technology when Earth comes under attack by the Goa'uld."
"Carter must find a way to save Earth from total destruction at the hands of the Goa'uld, who have turned the Stargate into a doomsday bomb. Rya'c joins his father on a mission to destroy the Goa'uld weapon."
"SG-1 boards an abandoned Goa'uld mothership that has mysteriously arrived in Earth's orbit, and must escape the doomed vessel when it crashes into the ocean."
"SG-1 investigates the discovery of a woman frozen in the ice in Antarctica, who may be a link to the gate builders. A mysterious disease threatens to kill everyone at the research base."
"Carter, Teal'c and Jonas investigate the death of a scientist with connections to the Goa'uld, and find a small town whose citizens harbor a dark secret."
"Jonas' people ask Earth for military aid in an impending war with their rival nations, but his former mentor offers another solution: a resistance movement ready for a coup."
"A news reporter threatens to expose a top-secret military project, but when Carter and Jonas give her a tour of the X-303, they discover that she is a pawn in a much larger plot."
"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."
"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."
"A near-death trial causes Teal'c to imagine his life as very different from the one he knows, where he is a normal person living on Earth -- until he can no longer distinguish reality."
"Prometheus is forced to land on an alien world, where the local Stargate is the team's only chance of returning home -- though the local population believe the gate to be a myth."
"The team finds an impoverished world enslaved by a Goa'uld underlord, but their plans to free it may be compromised when Jonas experiences unexplained visions of the future."
"SG-1 is called to defend the people of Abydos from the Goa'uld once again when they learn that Anubis, in search of a powerful device, is about to attack."
"While searching for the Lost City of the Ancients on a distant planet, SG-1 is stunned to find Daniel Jackson alive and in human form but stripped of his memory. O'Neill convinces Daniel to return with them to the SGC, where he is reinstated for a daring mission to destroy Anubis' powerful new super-weapon!"
"The team returns to Jonas' homeworld when they learn that the Goa'uld are after its naquadria. When Jonas is captured by Anubis, Daniel is his only hope."
"When Earth's attempts to exploit a newly-discovered naquadah mine are thwarted by a tribe of indigenous Unas, SG-1 must turn to an old friend for help."
"Major Carter joins an alien pilot for a space race, where the winner is awarded a lucrative contract with the planet's most powerful corporation. But the rest of the team discovers that there is more at stake than the finish line."
"The team investigates an unstoppable new enemy soldier engineered by Anubis. Dr. Jackson leads a team in search of an alien device in Central America, but gets more than he bargained for."
"O'Neill seeks help from a former comrade to rescue Daniel and Dr. Lee, who have been kidnapped in Central America. Carter, Teal'c and Jacob infiltrate Anubis' super-soldier facility."
"When the Kelownans discover that a massive underground vein of naquadah is being converted into naquadria, Jonas Quinn seeks help from Earth in avoiding the total destruction of his planet."
"Daniel is plagued by dreams of his former girlfriend, who has been taken as a Goa'uld host. Samantha Carter begins a romantic relationship with a detective, from whom she must hide her life at Stargate Command."
"Earth's secret offworld base is attacked by Anubis' forces, and Major Carter finds herself being hunted by the enemy. General Hammond and Jacob Carter make an unnerving discovery about the Earth-Tok'ra alliance."
"A film crew arrives to document the work of the S.G.C. for eventual disclosure to the public, but finds that the base's personnel are less than eager to participate."
"SG-1 is called into action while a film crew is documenting the Stargate program, but the S.G.C. comes under investigation after the mission goes terribly wrong."
"O'Neill goes to great lengths to keep the Ancients' knowledge from falling into Goa'uld hands when the team discovers a second repository. The President replaces General Hammond with a civilian diplomat."
"Anubis begins a systematic assault on Earth, and the planet's only hope of salvation depends on whether SG-1 can find the Ancients' mythical Lost City."
"Carter and Teal'c go in search of the Asgard to try and save Colonel O'Neill, but discover that the Asgard's enemy has returned with a vengeance. The System Lords seek an alliance with Earth against a common enemy."
"While the Goa'uld threaten to attack Earth, SG-1 and the Asgard make a last, desperate stand against the Replicators, which have captured Major Carter and invaded the last outpost of the Asgard civilization."
"The S.G.C. is put under quarantine after a mysterious infection leaves a Russian officer in the infirmary -- but the disease may not be a disease at all."
"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."
"The Stargate is stolen, leading SG-1 to discover that the Trust has taken control of an advanced ship in orbit. Teal'c investigates a series of wide-spread Jaffa deaths."
"A duplicate of Colonel Carter seeks help from Stargate Command in defeating the Replicator Fifth, who she claims has found a way to counter the Asgard's new weapon."
"The Replicators begin a systematic attack of the Goa'uld, forcing Baal to come to Earth for help. The Jaffa Resistance risk their entire movement in an attempt to retake a holy city in Baal's domain."
"The fate of the galaxy hangs in the balance as Sam and Jacob search for the only weapon capable of stopping the Replicator onslaught. O'Neill leads a defense of the S.G.C., while Daniel squares off against Replicator Carter."
"While Daniel finds himself in a mysterious diner suspended between death and ascension, Jacob's fate takes an unexpected turn, Jack and Sam consider their romantic lives, and Anubis unleashes his plan for galactic destruction."
"With the timeline changed by SG-1's actions in the distant past, an alternate version of SG-1 must use the newly-discovered time ship to set things right."
"An Air Force pilot attempts to reassemble SG-1 after they have gone their separate ways. An old \"friend\" arrives on Earth asking for Daniel's help in finding an ancient treasure -- and she won't take no for an answer."
"An Ancient communications device renders Daniel and Vala unconscious, sending their minds to another galaxy -- where they inhabit the bodies of two people persecuted by the followers of an evil religion."
"Daniel comes face to face with the Ori, a fiery race of beings who demand the worship of mortals. Elsewhere, Stargate Command encounters the first Ori missionary in our galaxy."
"SG-1 investigates when evidence suggests that there are still Goa'uld hiding on Earth -- including a former System Lord. Tensions between Earth and the Free Jaffa continue to mount."
"Colonel Mitchell is injured in a skirmish with a warrior from a mythic tribe of rebel Jaffa, and is trained in their fighting techniques only so that he may engage in a ritual battle to the death."
"SG-1 finds a genetically advanced Goa'uld-human hybrid created by Anubis, and returns him to Earth for study. But even keeping him alive may not be worth the risk."
"Earth is infected with a deadly Ori plague, prompting an ally from SG-1's past to come to their aid. Gerak proposes that the Free Jaffa follow the Ori religion."
"As the Ori plague spreads rapidly, SG-1 hopes that the Prior who caused the disease may hold the key to its cure. Gerak tries to rally the Jaffa to the Ori's cause, prompting Teal'c and Bra'tac to initiate a resistance."
"Multiple SG-1s show up at Stargate Command, leading the \"real\" team to conclude that they have each been inadvertantly displaced from different parallel realities."
"Baal kidnaps Teal'c as part of a plot to brainwash those Jaffa advocating a move toward democracy. Cameron Mitchell learns that an old friend is about to die."
"SG-1 is captured after a deal with the Lucian Alliance goes bad ... and the planet's Stargate goes missing. Meanwhile, a former System Lord attempts to rebuild his empire."
"Mitchell and Carter are shifted to another dimension, making them invisible to everyone at the S.G.C. Meanwhile, Teal'c and SG-9 discover that the Sodan have been brutally attacked."
"Vala Mal Doran makes contact with Stargate Command from the Ori home galaxy, and tells the story of her life undercover in a village of followers building the Ori's invasion fleet."
"SG-1 discovers the village of Camelot on an alien world, and must face Merlin's security system when they go in search of an Ancient weapon. Elsewhere, Earth and its allies assemble a fleet when a working Ori Supergate is discovered."
"As the Ori invade the Jaffa planet Chulak, Vala and Daniel must deal with their leader: Vala's young daughter, rapidly aged by the Ori to serve their purposes."
"SG-1 investigates a problem off-world and soon finds that they have become victims themselves: they cannot stay awake. Meanwhile, Vala Mal Doran undergoes an evaluation on Earth, hoping to join SG-1."
"Daniel and Vala travel to Atlantis in search of Merlin's anti-Ori weapon, while Sam, and Mitchell join forces with Dr. McKay to lock out the Ori supergate."
"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."
"SG-1 tries to defend a planet from the Ori by hiding its people in another dimension. Vala attempts to convince her husband Tomin of the Ori's true motives."
"An experiment gone wrong pulls Samantha Carter into a parallel reality, where she must save Earth from an Ori assault before she will be allowed to return home."
"When SG-1 discovers that Daniel Jackson has been turned into a Prior of the Ori, they must determine whether or not his plan to destroy the Ori is genuine."
"SG-1 realizes they have stepped through the gate into another planet's museum -- but are mistaken for a band of zealous rebels who have taken hostages."
"Trapped on board the Odyssey, the members of SG-1 must live out the rest of their lives together when Carter activates a time dilation field to save the ship from destruction."