O'Neill, Daniel, and Teal'c try to obtain intelligence on the little self-replicating robotic invaders in the submarine, but they are forced to fall back. With Daniel's new theory that the Replicators are made up of the same materials they consume, the Replicators may be eliminated through sinking the iron submarine as long as the surviving Replicator from Thor's advanced ship is destroyed beforehand. Meanwhile, Carter witnesses a short battle against the Replicators in the Asgard galaxy during which five Asgard ships are lost. Carter notices the Replicators' attraction to new technology and proposes to use the "O'Neill", an incomplete Asgard ship originally designed to fight the Replicators, as a lure to draw the Replicators into hyperspace and destroy them in the "O'Neill"'s self-destruct. Thor eventually accepts the plan, the Replicators take the bait and are destroyed.