Film Story :
Searching for the secret of gunpowder, twenty European mercenaries have traveled to China during the reign of the Renzong Emperor (AD 1010–63). A few miles north of the Great Wall, they are pursued by Khitan bandits, who have already killed some of the men. Upon escaping, they seek refuge in a cave but are attacked by an unknown monster, leaving only William and Tovar alive, with the former having slashed off the monster's hand. The two decide to bring the arm with them. The next day, they stumble upon the Great Wall and are taken prisoner by Chinese soldiers of a secretive military sect called the Nameless Order, led by General Shao and Strategist Wang. The Nameless Order is a Chinese military order commissioned by the Imperial Court of the Song Dynasty as a special division of the Imperial Army conceived for the sole purpose of repelling a horde of alien monsters who rise every sixty years. The commanding officers are shocked upon seeing the monster's severed hand, as the Order believed the invasion was still weeks away. Suddenly, a large wave of monsters attack the Great Wall, and the battalions are mobilized. The Nameless Order is divided into five special units: the melee-specialist Bear Troop, the acrobatic-specialist Crane Troop, the archer-specialist Eagle Troop, the siege engine-specialist Tiger Troop, and the horse-mounted Deer Troop. Losses are sustained on both sides before the monsters' queen recalls her warriors. During the battle, William and Tovar are freed by Sir Ballard, a European who, like them had ventured east twenty-five years ago in search of black powder. William saves Peng Yong, a warrior in the Bear Troop from the attacking monsters. William and Tovar's battle skills earn the respect of General Shao and Commander Lin, leader of the Crane Troop. Later, William and Tovar meet Sir Ballard who had also been taken prisoner and had been serving as an English and Latin teacher. The three foreign mercenaries discuss plans to steal black powder from the storeroom and flee while the soldiers are occupied in battle. Later, Wang meets William and explains the situation: the monsters that he fought were Tao Tei, which originated from a green meteor that crashed in Gouwu Mountain two thousand years ago. The Chinese believe the Tao Tei were sent from the gods to punish the Emperor for abusing his authority over the Middle Kingdom and its people. They attack northern China once every sixty years, an invasion for which the Order has been training for their entire lives. During the night, two Tao Tei reach the top of the Wall and silently kill several watchmen. Shao and Lin lead the Deer soldiers to investigate, but are ambushed. The Tao Tei are slain but Shao, wounded beyond recovery, succumbs to his injuries and dies, leaving Lin to take command of the Nameless Order. Around this time, an envoy from the capital arrives with an ancient scroll which suggests that the monsters are pacified by magnets. Wang believes that the stone William carried all this time enabled him to slay the Tao Tei he fought before entering the Wall. To test the hypothesis, William suggests that they should capture a Tao Tei alive and agrees to help. This results in his delaying his escape plans, which puts him at odds with Tovar who nevertheless delays his escape plan to assist William, much to Ballard's chagrin. During the next attack, the Tao Tei are numerous enough to cause Lin to resort to using black powder rockets, whose existence had been kept secret from the Westerners until now. They manage to capture a living Tao Tei and prove the hypothesis. The monster is taken to the capital by the envoy. A short while later, a hole is discovered in the base of the Wall, which the Tao Tei queen has used to lead her hordes to the capital. While Lin investigates, Tovar and Ballard try to escape and knock William unconscious for resisting. William is then arrested by the Chinese soldiers, and despite being saved by a statement from Peng Yong, William eventually is locked up in the Wall. Some distance away, Ballard betrays and abandons Tovar, but is himself captured by the Khitans, who inadvertently kill themselves and Ballard after carelessly igniting the powder. Tovar reclaims the horses but is recaptured by the Deer Troop. At the capital, the envoy decides to show their theory to the Song emperor, but the Tao Tei wakes up and signals to the Tao Tei queen. Knowing that the horde is approaching the capital, Lin orders the use of unstable hot-air balloons, to follow the Tao Tei. Before setting out for Bianliang, the capital, Lin passes the word to set William free, with Wang telling him to tell the outside world about the danger about to come, but William decides to stay and boards the last balloon with Peng and Wang. They arrive just in time to see Lin's balloon crash-landing in the now destroyed capital, and save her from being devoured. They land safely in the Emperor's palace, where Wang proposes an idea to kill the queen by tying explosives to the captured Tao Tei and giving it meat to be delivered to the queen. While transporting, a horde of Tao Tei breach the sewers. Peng Yong sacrifices himself to save the others. With the Tao Tei released, Lin and William climb the tower to shoot a black powder rocket and detonate the explosives. Wang sacrifices himself to buy time for Lin and William to move to the upper floors. Two of William's arrows are deflected by the Tao Tei queen's bodyguards, but Lin's spear breaches the defenses after William throws the magnet into the horde. The queen is destroyed, and the rest of the horde is frozen solid. With the horde destroyed, William is given an offer, during which he forgoes the powder and instead frees Tovar, much to Tovar's annoyance. The two, guided by cavalry, begin their journey back to Europe as Lin, now the General, watches over them from the Wall. William says that he wants to go back, but jokes with Tovar, saying he doesn't trust him going alone.