The Defiant encounters a planet surrounded by an energy barrier, in the Gamma Quadrant. Dax is eager to check it out, but as they penetrate the barrier, Kira is hit by a discharge. The crew is greeted by the inhabitants, who are their descendants, the result of an anomaly which caused the Defiant to crash on the planet, 200 years back in time. Kira - who learns of Odo's love for her from an older version of him - is destined to die unless she gets back to DS9. The crew must choose whether to let themselves be stranded and allow Kira to die, or to wipe out the existence of the colony.
