At the same time, from a place of nightmares--which Buffy and Faith share--a terrible evil invades Sunnydale, setting off a quarter of disasters: A controlled burn of some old forest growth escaltes into a raging fire that threatens to devour the town; astonishingly high tides at the beach take out boats, oceanfront property, and innocent bystanders; a hurricane pummels the beleaguered town, but does not quench the fire; and a massive earthquake erupts, disgorging pockets of natural gas from the huge sinkholes.

Clearly, these catastrophes are linked to the Slayers' nightmares, which resolve around four strangely swathed, indistinct figures. One is burning, one is dripping wet; one is covered in mud, one shourded in the windswept linen. Each trudges across pristine desert sand dunes, carrying a box of grafted skin and bone that Faith thinks she recognizes from a previous battle. Research leads Giles to the Watcher's Diaries, where he learns that the last Slayer to encounter a similar container was India Cohen--Buffy's immediate predecessor.

Strangely, Buffy has never given much thought to the young girl whose death activated her own era as the Chosen One. But now she must draw on the strength of those who came before her--or something else will draw on hers. For BUffy is being stalked by a monstrous force that journeys through time, fortifying itself by draining the primal power of a Slayer. Mortal though she may be, if she wishes to stop this demonic presence, Buffy must orient herself on continuum that predates even humanity itself.