London docks, twilight, 1850...Twelve-year-old Jack Harkett sees a huge ship sail into port. he also sees a flock of black creatures fly from the ship and disappear over the streets of London. He waits in the shadows, intending to board the ship in search of food, or money or anything he can sell. Instead he meets a boy of his own age...running for his life! Thus streetwise Jack meets the more bookish Benedict and the two become firm friends - and co-conspirators. Ben has seen and heard horrific things. Jack is fascinated by his story and determined to prevent similar things happening in his own city. Together they seek to defeat Camazotz - the vampiric bat god who destroyed the Mayan civilization that destroyed him. But Jack is a street urchin and Ben is an orphan. They have no one to turn to, and nothing to rely on but their wits and each other. Together, they face the Vampire Plagues...