Two doctors, the young, passionate and well-liked Osanai and the veteran, ambitious Tatsugaura, are both investigating the mysterious 'Monmow' disease, found only in one remote village, which causes bizarre bone deformation, making its victims take on a beastlike appearance before their deaths.

Osanai is sent to the village by Tatsugaura to see if he can find a cause for the disease while also treating the victims to the best of his ability. But in reality, Tatsugaura is scheming against Osanai and intends to infect him with the disease in order to clear the way of any obstacles of presenting his own research, and thus gaining high prestige and rank in the medical world.