Twelve-year-old Izzy has been haunted by the shadow of her ten-times-great grandmother for as long as she can remember. This is no ordinary ancestral ghost: This great granny was the first woman to be hung for witchcraft in Izzy's small New England town.

Every October first, tourists flood the streets of Marblehead. Unfortunately, this year so do a mysterious man and a possessed town psychic. When the man shows up at Izzy's family-run bookstore, making odd demands and threatening her mom, she must find the connection between this creep and her ghostly visions.

Trying to make sense of this chaos, Izzy roams into secret rooms, holds seances at the local tarot parlor, and digs through the old family cookbooks that sit on her shelves. When she discovers that she may be a part of a once-in-a-century ritual, Izzy must decide whether it's going to take baking magic or blood magic to protect herself and her parents from the return of the witch hunt.