"Asians" are a new species that gradually appeared in the human vision in the 1980s. They are derived from humans and have the same appearance as humans, but have an immortal body. Only after a human dies can it be determined whether he is an Asian. Humans are afraid of the powerful power contained in Asians and have launched a harsh hunt and research on them. Nagai Kei (voiced by Miyano Mamoru) is an ordinary teenager with superb IQ and excellent grades. One day, in a traffic accident, Nagai Kei unfortunately died and then became an Asian and was wanted by the military. With the help of his childhood friend Kaito (voiced by Hosoya Yoshimasa), Nagai Kei embarked on a journey of escape, during which he met the mysterious hat man Sato (voiced by Otsuka Yoshitada). Although Sato and Nagai Kei are both Asians, Sato does not know why he regards Nagai Kei as an enemy.