On Halloween in Salem, Massachussetts, Max Dennison (Omri Katz) has to take his younger sister, Dani (Thora Birch), trick-or-treating. Along with his new crush, Allison (Vinessa Shaw), they investigate the Sanderson cottage where three witch sisters—Winifred (Bette Midler), Sarah (Sarah Jessica Parker), and Mary (Kathy Najimy)—once lived.

Max lights the Black Flame Candle and inadvertently resurrects the witches. However, to continue to survive, the witches must suck the souls of children and they start with Dani, but she's rescued by Max. Venturing out, the witches discover to their horror that Halloween is now a holiday.