Halloweentown II Kalabars Revenge (2001)

The Cromwell clan lives in the real world except for their grandmother who lives in Halloweentown a place where monsters go to escape reality But now the son of the Cromwells old enemy Kalabar has a plan to use the grandmothers book to turn Halloweentown into a grey dreary version of the real world while transforming the denizens of the real world into monsters