The television series Stargate Atlantis premiered on the Sci Fi Channel, introducing audiences to the spin-off of Stargate SG-1.
The finale of the first season of Stargate Atlantis aired, concluding the initial storyline and setting up future developments.
The third season of Stargate Atlantis began airing, bringing new characters and expanding the story arcs.
The final episode of Stargate Atlantis aired, ending the show's five-season run after 100 episodes.
The Atlantis Expedition is launched from Earth to the Pegasus Galaxy, reactivating the Atlantis city base.
The Atlantis team encounters the Wraith for the first time and learns about their threat to human populations.
Stargate Command organizes a multinational team to explore the Pegasus Galaxy and investigate the lost city of the Ancients.
The team discovers a former Wraith named Michael who has undergone genetic modifications to become more human and allies with the Atlantis crew.
A major Wraith offensive attacks the city of Atlantis, forcing the expedition to mount a critical defense to save the city and its inhabitants.
The Atlantis Expedition establishes a tenuous alliance with the Genii, a technocratic human civilization in the Pegasus Galaxy.
The team discovers the Asurans, a new threat — a race of human-form Replicators created by the Ancients.
Efforts intensify to find a permanent solution to the Wraith threat, including technology upgrades and attempted suppressions.
The Atlantis Expedition is recalled, and the city is relocated back to the Milky Way galaxy after years of conflict.
