Southern Anatolia, 260 AD. The town of Edessa, a Roman outpost, is on its last legs, besieged by the Persian troops of Shapur I. Roman Emperor Licinius Valerianus agrees to meet his adversary to draw up a peace treaty, but it is only a trap and the Emperor and his twelve guards are chained and dragged away to work as prisoners in a solitary Persian turquoise mine. After months of forced labour the Emperor dies, but his guards make a daring escape lead by the heroic and enigmatic chief, Marcus Metellus Aquila. They meet a mysterious, exiled Chinese Prince, Dan Qing, and agree to safeguard his journey home to reconquest his throne from his mortal enemy, a eunuch named Wei. Thus begins the adventures of the Romans and the Prince as they journey to China. There they will discover that they aren`t the first of their kind to arrive in China: they were preceded centuries before by the survivors of the `lost legion`.