On December 10, 1968, the largest unresolved incident of the 20th century occurred in Fuchu, Tokyo, called the "300 million yen robbery". Although a major investigation was carried out with an unprecedented scale, it did not result in the arrest of the criminal. In 2009 in Nagasaki, Japan. Narumi Yamato, a senior high school student, was on his way to school with his friend Odagiri Miku, when they found a bloody trail and followed it.