Lucy likes to tell monster stories. She's told so many that her friends and her family are sick of it. Then one day, Lucy discovers a real, live monster: the librarian in charge of the summer reading program. Too bad Lucy's told so many monster tall tales. Too bad no one believes a word she says. Too bad the monster knows who she is... and is coming after her next.

While babysitting them, strange old Aunt Dahlia provides her nephews, Tom and John, with prune cookies that have a strange effect.

Cooper Holmes hears mysterious dogs barking in the night, then sees two evil-looking canines that disappear.