Captain Sisko and the crew of the USS Theseus team up with Starfleet Operative Kingsnake-a.k.a. Harry Kim-to stop the war-loving Tzenkethi from launching their fleet across the Quadrant. Unfortunately for Starfleet, however, the Tzenkethi leader has a surprise guest of his own who will stop at nothing to thwart Starfleet's plans. Meanwhile, when the crew is greeted by continuous-and frightening-earthquakes, Dr. Crusher realizes there is more going on with the planet than they may be able to survive.