The Carlsons move into their new dream home, but little do they realise there are monsters living in the basement. How long can Eddie hide Fiend, Haggis and Norman from the rest of the family?

Haggis is depressed and no one knows why. A therapist says he needs a father figure, so Nick reluctantly steps into the role. But when Nick starts to enjoy his time with his new monster son, Eddie and the other monsters start to get jealous.