Arthur Finkle, a quiet bookseller in small-town New England, shares his shop with an unlikely tenant: Horace, an ancient, grumpy entity living in the crawlspace who offers literary criticism instead of eternal terror. When Arthur unknowingly sells a dangerous book to a young girl, it awakens a shadowy force hunting for the volume. Now Arthur must team with the girl's mother and his otherworldly roommate to rescue her using the only weapons he has—courage, wit, and the right story at the right time. A heartwarming tale of found family and the power of words.