Richard Tyler (Macaulay Culkin) is a boy who is timid, and afraid of most things. His father Alan (Ed Begley, Jr.) hopes to help him by building him a treehouse, and sets out to do so. When he sends Richard off for some more nails, a strange storm rises, and Richard takes shelter in an old, apparently abandoned, library. Once inside Mr. Dewey (Christopher Lloyd), the seemingly crazy librarian taunts Richard about wanting some kind of book. When Richard heads off to find a phone, he slips on the wet floor and is knocked unconscious, awakening to find himself being transformed into an illustration from a book. Once there he meets three books: Adventure (voice of Patrick Stewart), Fantasy (Whoopi Goldberg), and Horror (Frank Welker). The books promise to help Richard return to the real world if he will check them out when he returns. In their journey to the exit, they encounter many difficulties, including an encounter with Dr. Jekyll and Mr. Hyde (both voiced by Leonard Nimoy). Their adventure will hopefully lead Richard back to the real world.