The Halliwell sisters are reunited in the grand Victorian home of their childhood. Phoebe discovers the Book of Shadows in the attic and when she reads the spell on the first page, their inherent magical abilities are activated. The sisters must try to keep their newly developed powers secret, while Prue's ex-boyfriend, Inspector Andy Trudeau, is investigating a serial killer whose victims are all witches. Piper narrowly escapes death when she discovers that her boyfriend Jeremy, an evil warlock, is the killer. When the sisters try their first spell, Jeremy is vanquished, and they discover the ancient Power of Three.