The Atlantis base is threatened when the team discovers that an alien entity is in the city. McKay grows worried when he is unable to remove an Ancient shield device.
McKay's efforts to harness the energy of an alien planet's atmosphere allows for a return trip to Earth – but the team may not be able to return to Atlantis.
The team finds a paradise world that would make an ideal sanctuary for those fleeing from the Wraith, but the local inhabitants believe their goddess will not permit it.
A woman is found in suspended animation in Atlantis, and the team is shocked to see that it is Dr. Weir herself, who tells them of her trip 10,000 years into the city's past.
Plagued by terrifying nightmares, Teyla begins to recall a time when she and her father were captured by the Wraith and subjected to disturbing experiments.
With a group of Wraith hive ships on the way to Atlantis, the team searches for a place to flee and a way to destroy the city. McKay leads a team to try and activate the Ancients' orbital weapons platform.