Adrift (2)
Floating in deep space with the city's protective shield failing, the team must do all they can to keep Atlantis alive. A radical injury threatens Dr. Weir's life.
More from Season 4
Episode 2
Lifeline (3)
Colonel Sheppard and his team embark on a risky mission to steal a Z.P.M. power module from the Replicators -- but must rely on a compromised Dr. Weir to succeed.
Episode 3
Reunion
When a group of Ronon's people enlist the team's help in raiding a Wraith weapons facility, Ronon reconsiders whether his future lies in Atlantis or with his friends.
Episode 4
Doppelganger
During an off-world mission Colonel Sheppard unknowingly becomes host to an alien entity, which infects others in Atlantis and afflicts them with terrifying nightmares.
Episode 5
Travelers
Colonel Sheppard is captured by the inhabitants of a generational ship and their beautiful leader, who wish to use his ability to use Ancient technology for their own ends.
Episode 6
Tabula Rasa
When a virus causes amnesia in everyone except Teyla and Ronon, the Atlantis team must work together to find a cure before their memories fade entirely.
Episode 7
Missing
During a visit to New Athos, Teyla and Dr. Keller find themselves on the run from a primitive tribe of warriors.
