Editing Stargate SG-1 (section)

== Series overview ==
{{Main|List of Stargate SG-1 episodes{{!}}List of ''Stargate SG-1'' episodes|Mythology of Stargate{{!}}Mythology of ''Stargate''}}
[[File:Stargate SG-1 cast minus Jonas Quinn.jpg|thumb|left|The series' main cast]]
The plot of ''Stargate SG-1'' picks up a year after the conclusion of the events recounted in the [[Stargate (film)|original feature film]]. It follows the adventures of SG-1, a military team from Earth. SG-1 and a dozen other SG teams venture to distant planets using an alien portal known as a [[Stargate (device)|Stargate]], which in the series is housed in a top-secret [[United States Air Force]] military base known as [[Stargate Command]] (SGC) in the underground [[Cheyenne Mountain Complex]] in [[Colorado Springs, Colorado]]. The mission of the SG teams is to explore the galaxy and search for alien technology and allies to defend Earth against alien threats such as the [[Goa'uld]] (a snake-like parasitic alien race from planet P3X-888 that takes humans as unwilling hosts), the [[Replicator (Stargate)|Replicators]] and the [[Ori (Stargate)|Ori]]. As explained in the series' backstory, the Goa'uld had transported human slaves from [[Earth]] to other habitable planets across the galaxy thousands of years ago and now pose as gods of old Earth mythologies, particularly [[Ancient Egyptian deities|Ancient Egypt]]. The series also draws upon [[Ancient Greek religion|Greek]], [[Roman mythology|Roman]], and [[Norse mythology]], as well as the [[Matter of Britain#Arthurian cycle|legend of King Arthur]]. SG-1 eventually learns that highly evolved human-like beings, known as the [[Ancient (Stargate)|Ancients]], had originally built the Stargate network millions of years earlier, before [[Ascension (Stargate)|ascending to a higher plane of existence]], after which they pledged not to interfere in the lives of other species.

=== Apophis Arc ===
{{Main|Apophis (Stargate){{!}}Apophis (''Stargate'')}}
[[File:NORADNorth-Portal.jpg|thumb|The [[Cheyenne Mountain Complex]] in [[Colorado]], United States is home to Earth's fictional Stargate Command in the ''Stargate'' universe.]]
The pilot episode ("[[Children of the Gods]]"), set one year after the events of the original feature film, introduces the Goa'uld [[System Lord]] [[Apophis (Stargate)|Apophis]] ([[Peter Williams (actor)|Peter Williams]]) as the main antagonist when he attacks Earth's mothballed SGC military base through the Stargate and kidnaps an airman. The SGC is brought back into action when the Stargate is revealed to be part of an interplanetary network connecting countless planets. SG teams are created to help defend Earth against the Goa'uld, who have interstellar pyramid warships and vast armies of [[Jaffa (Stargate)|Jaffa]] (hereditary slaves and human incubators to the Goa'uld) at their disposal. Earth's flagship team SG-1, which includes Apophis's defected First Prime (lead Jaffa soldier) [[Teal'c]], initiates several alliances with other cultures in the galaxy, such as the Goa'uld-like but truly symbiotic [[Tok'ra]], the advanced human [[List of recurring alien characters in Stargate SG-1#Tollan|Tollan]], the pacifist [[Nox (Stargate)|Nox]], the benevolent [[Roswell Incident|Roswell]]-alien [[Asgard (Stargate)|Asgard]] and remnants of the powerful Ancients. Another alien threat arises in the [[Stargate SG-1 (season 3)|Season 3]] finale ("[[Nemesis (Stargate SG-1)|Nemesis]]") in the form of sentient machines called [[Replicator (Stargate)|Replicators]]. Meanwhile, rogue agents of a shadowy intelligence agency on Earth, the [[NID (Stargate)|NID]], repeatedly attempt to take control of the Stargate and other alien technology. Despite Apophis's death in the [[Stargate SG-1 (season 5)|Season 5]] premiere ("[[Enemies (Stargate SG-1)|Enemies]]"), the [[Goa'uld Empire]] remains a major foe in ''Stargate SG-1'' until the end of [[Stargate SG-1 (season 8)|Season 8]].

=== Anubis Arc ===
{{Main|Anubis (Stargate){{!}}Anubis (''Stargate'')}}
After Apophis's defeat, the half-Ascended Goa'uld System Lord [[Anubis (Stargate)|Anubis]] ([[David Palffy]]) assumes the role of the primary antagonist of the show. This new villain possesses much of the knowledge of the Ancients and their technology. While Earth builds its first interstellar spaceship (the ''[[Prometheus (Stargate)|Prometheus]]'') in seasons [[Stargate SG-1 (season 6)|Season 6]] and [[Stargate SG-1 (season 7)|Season 7]], Anubis creates an army of almost invincible [[Kull Warrior]]s and wipes out or subordinates most of his adversaries amongst the System Lords. In the Season 7 finale ("[[Lost City (Stargate SG-1)|Lost City]]"), SG-1 discovers a powerful weapon in an Ancient outpost in Antarctica that annihilates Anubis's entire fleet and also sets the stage for the spin-off series ''[[Stargate Atlantis]]''. Ba'al subsumes much of Anubis's power in [[Stargate SG-1 (season 8)|Season 8]], while Anubis, who survived the destruction of his fleet in a disembodied form, quietly begins to re-assert his influence. Human-form Replicators begin to conquer the System Lords, but SG-1 finds and adjusts an Ancient weapon to destroy all Replicators throughout the galaxy. Near the end of Season 8 ("[[Threads (Stargate SG-1)|Threads]]"), it is revealed that the benevolent Ascended being [[Oma Desala]] ([[Mel Harris]]) is responsible for Anubis's original ascension. When she engages Anubis in an eternal stalemated battle on the Ascended plane to prevent his acting on the mortal plane, the Replicators and most System Lords have already been annihilated and the Jaffa win their freedom from Goa'uld rule.

=== Ori Arc ===
{{Main|Ori (Stargate){{!}}Ori (''Stargate'')}}
The original SG-1 team disbands after the events of Season 8, but slowly reunites under new team leader [[Cameron Mitchell (Stargate)|Lt Col. Cameron Mitchell]] after the SGC inadvertently draws the attention of the Ori to the existence of sentient life in the Milky Way; the Ori are revealed to be a faction of ascended Ancients residing in another galaxy that are diametrically opposed to the Ancients' belief in strict noninterference in the lower planes of existence, sapping the energy from untold billions of "lower beings" (non-ascended sentient beings) by means of their worship in a religion called Origin. While the Ori send enhanced human beings named [[Prior (Stargate)|Priors]] to the Milky Way to convert the galaxy to Origin, Ba'al and some minor Goa'uld infiltrate Earth through ''The Trust''  (a coalition of rogue NID operatives) to rebuild their power. At the end of [[Stargate SG-1 (season 9)|Season 9]] ("Camelot (Part 1)"), the Ori begin an evangelistic crusade with their warships and effortlessly wipe out the combined fleet of Earth and its allies. The leader of the Ori, [[Adria (Stargate)|Adria]] ([[Morena Baccarin]]), is introduced in the premiere of [[Stargate SG-1 (season 10)|Season 10]] ("Flesh and Blood (Part 2)"). SG-1 searches for the Sangraal, an Ancient weapon that might defeat the Ori, while Ba'al and his clones attempt to find the weapon for their own purposes. With the help of the powerful Ancient [[Merlin (Stargate)|Merlin]] ([[Matthew Walker (Canadian actor)|Matthew Walker]]), SG-1 finds the construction plans of the Sangraal and sends a working version to the Ori galaxy. Shortly thereafter, Adria ascends. The direct-to-DVD film ''[[Stargate: The Ark of Truth]]'' ends the Ori Arc. The only influential Goa'uld in the last two seasons of ''Stargate SG-1'' is the System Lord [[Ba'al (Stargate)|Ba'al]] ([[Cliff Simon]]), who is defeated in the direct-to-DVD film ''[[Stargate: Continuum]]''.