Whentheirmotherishospitalizedinacaraccident,PimandPuttsuddenlydiscoverthattheyhaveasetofgrandparentsthey'veneverknownabout.Butaterrifyingtruthhaslongbeenhiddenwithinthewallsoftheirgrandparents’house,atruththatgraduallyrevealsitselftoPimandPuttthroughamysticalhole,unleashinghair-raisinghorrorontheirfamily.