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.

After a team from Atlantis goes missing, the expedition finds itself in the middle of a Genii coup.

A charismatic Jaffa leader seeks to forge an alliance between Earth and his rebel followers, winning the allegiance of Teal’c and Bra’tac.