Jared Kane of the Rand Protectorate, from the planet Tegalus, makes contact with SGC against the wishes of his government and comes through the Stargate. Jarrod reveals a Prior made contact with Tegalus and gave his government plans for an orbital weapon…which they've used against their enemies, the Caledonians. The Rand have given the Caledonians five days to surrender, and the Prior told the Rand to refuse to deal with Earth any more as well. Jared hands over the early and partial schematics of the weapons, and wants SG-1 to destroy the weapon. Jared admits he hasn't lost his hatred of the Caledonians, but he doesn't want anyone on his planet killed on behalf of the Ori. Mitchell is skeptical but Daniel points out they're the ones who helped start the war (in "Icon"). Mitchell wants to blow up the weapon but Daniel would rather convince the Rand what the Ori really are.
Sam is studying the plans and believes the weapon is that efficient, with a significant lag time in the fire sequence. They plan to take the Prometheus to destroy the satellite if Daniel's diplomacy fails. Daniel updates Jared after contacting the Rand government and notes they're surprised by Jared's actions. Jared also reveals that Leda, Daniel's friend, was killed in a plague after refusing the Prior's healing powers. The Rand government agrees to meet with Daniel but he and Jared are imprisoned upon arrival. President Nadal confronts them and announces they are enemy of the states and will be detained until trial…if they're lucky.
As the Prometheus approaches, the Rand military commander, Commander Pernaux, confronts Jared and wants to know who is working for him against the government. The Prometheus emerges from hyperspace and locks on to Daniels's locator beacon, but he's not attached to it when they beam it up. They lock on to the satellite and the Caledonians get word of the ship's approach. Mitchell and Colonel Pendergast believe they should fire but before they can decide the satellite charges up. They fire missiles but impact harmlessly against its new shields. The satellite opens fire, slicing through their shields with ease. They scramble a fighter wing, with Mitchell and Teal'c in one of the F-302s, to attack the satellite but its shields hold. Sam works to reroute the ship drives to get them out of there. The satellite fires again, crippling the Prometheus, and Sam can't get to Auxiliary Control to make repairs. President Nadal refuses to offer surrender and gives the order to finish them.
Sam manages to get to another power relay station but doesn't have enough time to make repairs. Pendergast contacts the Rand to surrender while Mitchell has the fighters intervene between the Prometheus and the satellite. Nadal takes Pendergast's transmission and demands that Daniel and Jared confess their involvement with the Caledonians before he'll accept the ship's surrender. There's nothing Daniel can tell them and Sam is out of time – she gets them enough power to beam the crew down to the planet. Pendergast remains behind to handle the beam-out commands and Sam stays to maintain power. Nadal fires the weapon and the Prometheus is destroyed with Pendergast still aboard.
Pernaux confronts Daniel and Jared and is somewhat sympathetic, but is reluctant to go against the power of the Ori. The Prometheus survivors have been recovered by the Caledonians and SG-1 is reunited – Sam managed to beam out at the last minute. They meet with Minister Chaska of the Caledonians, who announces they have no intention of surrendering to the Rand. Sam works with more advanced schematics of the satellite and figures that they can disrupt the Rand control facility then the satellite is vulnerable to fighter attack. The Rand have an early-warning radar system and the control facility has proven immune to infiltration, but Sam proposes they can use an EM pulse to disrupt communications, and is aware that the detonation of an F-302 generates a miniature EM pulse. They can hook up a fighter's inertial damper to a Caledonian missile to generate a cloaking field and an EM pulse.
Nadal manages to get word of the missile launch, even if they can't spot the missile, and orders the satellite to fire two days early, over Pernaux's objections. Nadal contacts Chaska who denies anything while stalling so the missile can get there. Nadal appears to buy it but Chaska is skeptical. Nadal is getting word of visual reports of the missile and are sensing the F-302 that Mitchell and Teal'c are flying in to attack the satellite. Nadal activates the missile shields…too late. The power cut outs and they've lost contact with the satellite, and the F-302 is one minute away.
Nadal has Daniel and Jared brought before him and offers to call off the attack as a good-faith sign so they can reach a diplomatic solution. The Rand offer the Caledonians the Stargate in return for the satellite being left intact. Then there will be a ceasefire while the Caledonians can evacuate to another planet. Minister Chaska isn't buying it but Sam points out there's only so much they can do, and finally Chaska agrees. Mitchell withdraws as the back-up power comes on at the Rand facility. Nadal activates the satellite and prepares to fire on the Caledonian capital, over Pernaux's objections. Pernaux overrides Nadal, who has clearly lost it, and shoots Nadal before being gunned down himself. Nadal is dead and Pernaux becomes the new president although badly wounded.
Back at SGC, Mitchell meets with Daniel after delivering the letter to Pendergast's family. Daniel informs Mitchell that the talks between the two countries broke down and they can't contact either side. The Caledonians launched an attack and the Rand responded, and the Stargate is presumed buried in the rubble.