Ghoulia is a typical little girl . . . who happens to be a zombie. She lives in Crumbling Manor with her Auntie Departed and albino greyhound named Tragedy.

Crumbling Manor is all a-tizzy with glee as everyone prepares a party to die for to celebrate the return of Ghoulia's parents. Snooping through her grandmother's closet for a pretty outfit to wear, Ghoulia finds an old, beautifully crafted bracelet . . . which happens to unlock a hidden stairwell in the library!

Led to a locked door that can only be opened by solving a riddle and finding the door's mysterious "heart key," Ghoulia, her grumpy cousin Dilbert, and the wise greyhound, Tragedy, start their search for the missing key.

As clues start piling up, Ghoulia and Dilbert learn of their missing Auntie Acid. Suffering through a tragic heartbreak, their aunt left the manor many years ago and never returned. Detective senses tingling, Ghoulia suspects that their long-lost aunt may hold the "heart key" that unlocks the secret sealed door.

Gathering up their courage and wits, Ghoulia, Dilbert, and Tragedy leave the manor and embark on an adventure to find and bring Auntie Acid home! But will they be able to track her and the key down? Or will their sleuthing reveal too many secrets the zombie family wanted to keep locked away . . . forever?