 McKay, Sheppard, Beckett and Weir are on their way back from Earth on the Daedalus, which has arrived in Wraith space. The crew has been selecting new members for the team and Weir had a tough time to keep Sheppard in command of the military. He s now a lieutenant colonel. She also had a problem in her personal life. Suddenly one of the new team members, Dr. Monroe, dies of a power surge. At first it seems like an accident, but McKay has his doubts. Then he sees Lindstrom, another scientist, suddenly fly out of an airlock after he mentions he found the problem. There s definitely something wrong and McKay soon finds out the ship is infected by a Wraith virus. It s trying to take over the engine and other systems and is already sending a signal to call in the Wraith.