Eight days before Halloween, two strangers drive into the tiny town of Dunes, Michigan, in the middle of the night. After marking various locations on a map of the town, the two men take up residence on Willows Drive in the abandoned Kalaski Mansion.
At the nearby assisted living home, eighteen-year-old Greg Snow, who lives across from the Kalaski Mansion, helps decorate for Halloween. When he returns home, the two men—called Kasper and Ghoul—react strangely to the boy. They look at him as though he’s the spook in town. Their curious reaction makes Greg wonder what these men are up to. He shares his worries with his friends, and they soon make the acquaintance of a glowing orb named Rebecca, who tells them Kasper and Ghoul are there to destroy the town.
The new arrivals are in Dunes to seek the revenge for past slights. Their intention is to find the one person who stopped the process when they were last in town and destroy him and his family. Greg and his friends are willing to fight for their town—but Greg has no idea that he has a close family connection to the mysterious men.