Lieutenant Dax and Chief O'Brien have been taken prisoner by the Dominion and the Jem'Hadar have rendered the USS Defiant null and void. The only ones to survive the attack between the Defiant and the Dominion were Major Kira and Odo, who was able to escape with the unconscious Major on a shuttlecraft. Drawn by an unknown power, Odo takes the shuttlecraft to the Omarian Nebula. There, Odo and Kira come across an M-Class planet that is the home of the Changlings.