The new race that stole the device, not to mention Rodney and Daniel, turns out to be an old one meaning very old and well known to the human race. With an ancient grudge to settle they force Rodney to activate the device against the Wraith with a side effect that could kill millions through out the galaxy. That make the Wraith mad so they abscond with the Daedalus to retaliate. Once again we lowly humans have to take control of a messy situation to keep the master races from wreaking havoc in the galaxy.
Sheppard and Zalenka survive the explosion in the gate room and are on the mend in the infirmary. They soon set off in pursuit of Todd the Wraith who is in control of the Daedalus. McKay and Jackson meanwhile are still prisoners and now face the prospect of their captors forcing them into actions that will have dire consequences for the entire Pegasus galaxy. Sheppard is surprised at the relative ease with which they manage to take control of the Daedalus but soon realizes why: Todd the Wraith has locked in a course that will have the ship crash into the planet and destroy the device that is causing them so much harm.
- Dr. Daniel Jackson and Dr. Rodney McKay have been forced to reactivate the Attero device, a machine designed thousands of years ago to annihilate the Wraith. In doing so, they discover the reason the device was ultimately abandoned by its Ancient creator. While destroying Wraith ships that attempt to travel through hyperspace, the weapon inadvertently causes active stargates to self-destruct.
Meanwhile, Todd and his troops continue to hold Woolsey, Keller, Ronan and the Daedalus crew captive, convinced that they are behind the resurrection of this deadly technology. Fearing that if Todd succeeds in destroying the device, Jackson and McKay will most certainly be killed in the process, Sheppard calls on some old allies to help him rescue his friends.