At the end of World War II, a secret human experiment was being conducted in Manchuria, which was in the sphere of influence of the Japanese military. One man's face was to be transformed into that of a completely different person through plastic surgery. Shortly after operation, Japanese military facility where the man was staying was involved in a battle and collapsed, and he disappeared. In 1948, a letter of warning from the Twenty Faces was posted on the wall of the Japanese Museum. The notice read, “All national treasures will be taken away. The police, aware of the warning letter, rush to the Japanese Museum...