SG-1 is doing recon on a planet where Adria (Morena Baccarin) appears, now the fully-grown leader of the Ori Army. Meanwhile, unbeknownst to SG-1, the Jaffa have modified the Ancient device SG-1 used to destroy the replicators so that it now unmakes all living beings. The Odyssey beams SG-1 off the planet just before the Jaffa's new leader, Se'tak, deploys the Ancient weapon. Se'tak believes the weapon is the Jaffa's only means of battling the Ori, regardless of the casualties. SG-1 takes the opportunity to investigate the unmanned, unguarded Ori mothership left on the planet's surface. As a precaution, Teal'c and Mitchell plant C-4 explosives in the ship's power generation chamber, but are then taken prisoner by Jaffa forces led by Bo'rel, who arrives and claims the mothership in the name of the Jaffa. Meanwhile Landry (Beau Bridges) goes to Dakara to convince Se'tak to stop using the Ancient weapon. Back on the ship, Jaffa warriors capture Vala (Claudia Black) and Daniel (Michael Shanks) but Adria, who survived the Ancient weapon because of a powerful protective amulet she wears, intervenes. Adria intends to eradicate the weapon as she recognizes its power to prevent the Ori's conversion the entire galaxy. When she discovers the weapon is on Dakara, she flies the mothership there. Mitchell (Ben Browder) and Teal'c (Christopher Judge) realize their only chance at saving Dakara may be to destroy the Ori mothership, with SG-1 on board.