Nearly 2300 years ago, inside Vietnam's ancient Co Loa Citadel, King An Duong raised a massive fortress of enormous spiral walls and believed an enchanted crossbow made his empire untouchable. Then an ambitious enemy prince entered his royal court, married his daughter and stole the secret that protected the kingdom. What followed was an epic tale of domestic espionage and supernatural vengeance, ending with a murdered princess, a grieving traitor and a king who was swallowed