Fairy Bai Dong, who appears to be an old man but has only been training for 150 years (miniscule in fairy time), sees that the people of Earth are suffering because of intrusions from the world of Evil. He and a young assistant, Lu Jan, set up a medical facility on earth to help the people, taking the name Bu Dong (Bai Dong means All-Good). He also takes under his wing the impoverished scholar Shuang De, who lives in a temple where he trains two sisters, Qing Er and Cai Er, in the ways of God, for they are human girls raised by Evil spirits.