A team of scientists think they have found the location of the long lost city of Atlantis. It can be reached by a Stargate address that leads to the Pegasus galaxy.
Rodney can't remove an Ancient device that makes him invincible but prevents him from eating or drinking. Meanwhile, there are power malfunctions throughout the city and one of the Athosians mentions seeing a shadow.
Sheppard gets bitten by a Wraith-like bug and is dying. While the puddle jumper returns, it gets stuck in the Stargate. There's 38 minutes to find a solution.
Atlantis wants to trade food with the Genii, a simple civilization who turn out to be not so simple. They are planning a nuclear attack against the Wraith.
McKay and Weir start repairing the grounding station, while Sheppard tries to fight Kolya. The puddle jumper on the mainland enters the eye of the storm.
Major John Sheppard, Dr Rodney McKay and two other scientists explore a planet where a Wraith spaceship, which crashed there 10,000 years ago, during the Atlantis-Wraith War, is still sending an SOS signal.
It's Elizabeth's birthday and she gets a very special gift: a woman who has been in stasis in an Atlantis' laboratory for 10,000 years and is actually herself.
McKay finds a way to send a message to Earth, leaving space for personal messages. Sheppard and Teyla are off to spy on the Wraith fleet approaching Atlantis.
Teyla is haunted by nightmares, leaving her agitated. After seeing a psychologist, an old Athosian woman tells her a secret about her ability to sense the Wraith.
McKay and Zelenka come up with a plan to repair the Ancients' weapon satellite. Bates and Teyla get into a fight. He is found unconscious and badly injured shortly afterwards.
All hope seems lost, until Colonel Everett arrives suddenly from Earth. He is determined to defend the city until the arrival of a ZPM, brought by a new ship.
