Dr. Rush directs a shuttle to a planet inaccessible by Stargate – but a crash landing threatens to strand those on board. Meanwhile, Rush makes a stunning discovery on Destiny, and Young must decide what to do with his prisoners.
Chloe's increasingly erratic behavior leads the crew to suspect that she may be under alien influence. Eli returns home when he learns that his mother has fallen ill, and Camille finds Sharon struggling in her absence.
When Young and Rush are trapped on an abandoned alien ship, Rush has Amanda Perry brought on board in an attempt to steer Destiny to them while keeping his secret.
Simeon makes his escape from Destiny, sending Nicholas Rush on a vengeful mission to catch him. But Young and Greer must attempt to retrieve Simeon unharmed.
Members of the crew left behind in another galaxy make a shocking return to Destiny, while Chloe deals with the inevitable consequences of her transformation.
With Destiny up against a fleet of drones, the crew is surprised by the arrival of an old foe. Chloe faces her former captors when the crew decide to hand her over.
Rush expresses concerns when Earth approves Eli's plan to dial the Stargate home from inside a star – and is proved right when a duplicate of himself shows up with a warning from the future.
Chloe's body is taken over by the mind of someone the crew believed was dead. Meanwhile, T.J. must perform a dangerous transplant when Dr. Volker is diagnosed with an illness that threatens his life.
Homeworld Command tries to convince an ally occupying a naquadria-rich planet to let them try to dial Destiny, but suspects that they have already been infiltrated by the Lucian Alliance.
While attempting to return a group of colonists to their home, the crew finds records of their own alternate lives – and a planet on the verge of seismic destruction.
Destiny is attacked by drone ships while attempting to recharge its power reserves, forcing most of the crew to gate to a nearby planet while Eli tries a risky alternative.
Cut off from every star and every planet in their path, the crew takes a stand against the drone command ships. Meanwhile, Eli comes up with an extreme plan to escape drone space for good.
