During an investigation of a planet leveled by a Wraith attack, McKay and new security team member Lt. Laura Cadman are transported aboard a Wraith Dart, which subsequently crashes. Unfamiliar with the Wraith technology, Atlantis scientist Dr. Zalenka is only able to transport McKay out of the rubble. Cadman's body is nowhere to be found. Zalenka believes that she is still trapped inside the Dart, until McKay claims to hear her voice – coming from inside his own head! It seems that Zalenka's experiment, rather than saving the two separately, caused them to unite – and Cadman must remain inside of McKay's head until Zalenka can figure out a way to separate the pair. Meanwhile, as Ronon Dex settles in at Atlantis, he shows off his impeccable fighting skills during arsenal training. Impressed, Sheppard implores Weir to put aside her reservations about the newcomer and consider allowing Ronan to join the Stargate Atlantis team.