Ren Brothers

Rendi, Renjie , and Renmei , known collectively as the Ren Brothers, were a trio of masters of the Way of the Open Hand in Shou Lung. They developed tools for attaining immortality and compiled their knowledge in The Book of Inner Alchemy.

History
Over the course of their long lives, the three masters developed the Open Hand further, transforming its martial arts techniques into tools for attaining immortality. However, to do this, the Ren Brothers carried out gruesome experiments on captured animals and people for their research and development, producing rituals for fashioning magic items and magic weapons to enhance combat prowess and shortcut the process of becoming immortal. The most terrible item was the gloves of soul catching, which required the sacrifice of three great people to craft and their necromantic power permitted one to drain life from others; this at least was only a theory they never tried to actually make. They compiled their research and discoveries in The Book of Inner Alchemy and kept it to themselves.

Regardless, rumors of an ancient book holding the secrets of immortality through martial arts spread through the martial world and the Ren Brothers expected many would come hunting for it. Although conflicted in their need to preserve their knowledge and their guilt of using it, and fearing the chaos such knowledge would cause in the world, the Ren Brothers placed it in the immense Candlekeep library, on the Sword Coast of Faerûn on the far side of the continent, hidden and forgotten amongst countless other books. Exactly when it first appeared in the library was lost to history, but it remained there for centuries and was known to be one of the oldest works there by the late 15 century DR.

Background
The Ren Brothers are named for the Shaw Brothers: Runje Shaw (or Shao Renjie), Runme Shaw (or Shao Renmei), and Runde Shaw (or Shao Rendi), along with Run Run Shaw (or Shao Yifu). The Hong Kong–based Shaw Brothers Studio made countless classic kung fu movies.