Base on the true story, the movie star Jack Chan and John Cusack telling the first alliance between the Roman Empire and China Empire, 2000 years ago. 1900 years ago the 9th legion of the Roman Empire disappear nobody in the west knows what happened to them, till matching up with Chinese sources in the 21st century.
The 9th legion under the command of General Lucius (John Cusack) flee to the east to protect Publius heir of the Roman consul for the Parthian Empire to save him from death and a ploy by his older brother, Tiberius, who schemes to takeover the position as heir. There he met a Chinese General Huo An (Play b Jackie Chan) whom was in command of the Chinese legion station at the outpost of China's western boarders.
Together Huo An and Lucius must fend off Tiberius's men and escort Publius to China, where he can be safe.
Most detail of the actual historical event have already been lost, so most of the details of this movie is made believe (just like movies about the Trojan war, because most detail are lost, only the out line is base on history, the detail are all fiction) however, it have been confirm by both eastern and western historians, that a western legion protecting a young boy name Publius did came to China to seek asylum around 1900 years ago and base on all evidence both eastern and western historians are confident, they are the lost 9th legion of the Roman Empire.