Suspecting that someone is stealing from him, the aging and eccentric James Delacorte wants librarian Charlie Harris to do an inventory on his rare book collection. Soon after they begin, Delacorte is found dead at his desk, leaving Charlie with the bigger task of solving his murder. Immediately Charlie is suspicious of Delacorte's own family, and relies on the help of his rescued Maine coon cat, Diesel, to paw around for clues.
