During the Bite-Centennial, the ghouls discover an old scientist's workshop and travel back 200 years to the beginning of Monster High. But when they try to get home, they go through a vortex that fuses some of the ghouls together! With the help of the Hybrids, the new monsters in school, they learn how to control their combined flaws and together face their greatest challenge... saving Frankie!

"Based on the new movie"--P. [1] of cover.