Young brown-haired Jennifer Hart is the assistant librarian in Meadville, working under Miss Spaeth, the gray, unsmiling woman who had run the library for several years. Little does Jenny realize the adventure and danger in store for her when a copy of Alice in Wonderland is willed to the library along with many other books, the property of Mrs. Heading, a reclusive and odd newcomer to town. The book is a first edition, and might be worth thousands of dollars. And it disappears! Suspicion points to Jenny, and she receives several threatening and disturbing poison-pen letters.
When big-city newspapers reveal that Mrs. Heading was a former actress, rumored to have buried a fortune in her house, the quiet of Meadville is disturbed by transients. They include Andy Hartlaw, the new golf pro at Sunny Acres, the club Jenny belongs to, Roselle Lawton and her brother, Norman, and many others.
Jenny's problems are just beginning. Dr. Martin Robins, her mother's physician, whom Jenny unaccountably detests, badgers her for dates. Her free time is occupied in deciphering a cryptic message in the returned Alice, which Mrs. Harding had left specifically to her in her will. When Jenny explores Mrs. Harding's dusty, musty old mansion, accidents beset her. Someone is out to harm her, and she does not know who. Can it be her best friend, Derrill McClean, who seems to want to get her into trouble?
With the help of kindly Chief Kelly, the chief of police, Jenny solves these problems and comes up with a solution to her romantic entanglements at the same time.