The day the Turner family gets their very own monster is a momentous event in the neighborhood. Everyone gathers for the occasion. The monster can roar louder than a lion, leap down the stairs better than any Slinky, and eat grass so no one needs to mow. Based on the Turners' experience, investing in a monster seems like a great idea! Except, the monster that shows up isn't the monster they ordered at all. Their monster likes to pull pranks and paint murals, and when he eats grass, he gets gas! He isn't a good baker and he smells! Will the family return their defective monster? Or will the monster find a way to win their love?