The Dali Dynasty valued Buddhism over martial arts, and the royal family valued "crane bones" - those born with six fingers or a red mole between their eyebrows were regarded as the reincarnation of the Buddha. When the sweeping monk of Yunqi Temple picked up the bamboo slips inscribed with "Crane Bones" in front of the Buddha, he didn't know that he was about to be involved in a secret that spanned three dynasties. He also didn't know that Ruan Qingluan, the medicine seller who always came to the temple to ask for signatures, was actually a "Crane Bone Traitor" wanted by the royal family.