In the dark, foreboding sewers of Deptford, a mysterious entity known as Jupiter, Lord of All, reigns supreme, worshipped by a horde of rats who cower in its presence. Into this world of fear and darkness wanders a small, frightened mouse named Albert, unwittingly triggering a chain of events that will hurl his fellow mice a world of terror and heroic adventure. As the rats seek to summon the demon hordes and bring about the end of the world, the Deptford Mice must confront treacherous enemies and ancient magic in a battle to save London and the world from eternal darkness.