Christmas is almost here, and the Christmas sleepover at the public library may be canceled because strange noises in the library cellar have led to rumors that the library is haunted--so Abby and her friends set out to catch a ghost.
Puzzled over what to write for a creative writing contest, Abby finds inspiration when her dog digs up an old key on a gold chain and she sets out, with the help of Mrs. Mackenzie the public librarian, to solve the mystery of the golden key.
A lot of Abby's favorite books have gone missing at the local public library and she suspects a strange man that she has seen there but Jeremy, the bully in her class, and his four-year-old hyperactive brother Evan are complicating her investigation.