Lindy Powell finds a ventriloquist dummy in the dumpster behind a house and decides to call it Slappy. Lindy is soon being offered $20 to perform at birthday parties and Kris, her twin sister, begins to ask her parents for a dummy of her own. Mr. Powell brings home another ventriloquist dummy for Kris that she calls Mr. Wood and the two dummies come to life and start doing evil things.