William and the Clockwork Devil

After the death of his mother, a young man named William finds himself transported to another world. This strange place seems like the Middle Ages, but the villagers are threatened by mechanical monsters and centaur highwaymen. A masked doctor explains that poison has driven the kingdom mad, and William is the only remaining knight. Is the doctor trustworthy, or has he been struck with the madness, too? William must choose between pretending he's brave enough to battle an invincible clockwork dragon, or letting the masked doctor "cure" him with medieval brain surgery.