ThePotterfamilyhasjustmovedtoarentedapartmentinSanFrancisco.HarryPotterSr.andhiswifeAnnearebringingthepackagestotheapartmentandtheirsonHarryJr.andtheirlittledaughterWendyAnnestaysonthesidewalk.Wendygoestothelaundryroom,shemeetsthewickedtrollTorokthatuseshismagicringtopossessWendyandtouseherformtotransformthedwellersandtheirapartmentintoothertrollsandhiskingdom.HarryJr.feelsthatsomethingiswrongwithhissisterandseeksouthelpwiththegoodwitchEuniceSt.Clairthatlivesinthebuilding.