Klingon Dahar Master Kor, Jadzia Dax, and Worf search a remote planet in the Gamma Quadrant for the fabled Sword of Kahless; the mythical, millennia-old weapon of the Klingon Empire's first leader.

After the bombing of a Federation conference is revealed to be the work of the Dominion, Sisko and Odo travel to Earth in hopes of uncovering the Changeling responsible.