Hercules Amsterdam is only three inches tall—the perfect height for exploring the hollow spaces behind his bedroom wall. Deep within the walls, little Hercules discovers a fanciful city full of mice and falls in love with their friendly, carefree ways (imagine mice cream every day!). But when Hercules stumbles across abandoned mice cities that look like war zones, he realizes that the happy mice face a frightening and grotesque hidden enemy—rats! Hercules is determined to protect his sweet, gentle friends. Join him on his journey to foil the evil rats for good—and save mousekind as he knows it.