BLOOD: THE LAST VAMPIRE tells of the horrific events which took place in a U.S. military base in Japan, just before the Vietnam War. It seems that the populace of Yokota Air Base is unknowingly suffering from a series of vampire attacks. Unknowingly, because the victims then show up as suicide casualties. So in comes the mysterious Saya, who works in concert with a covert government agency in hunting down these vampires, which are actually blood-sucking demons called the Chiropterans. Posing as a high school girl, Saya begins to nose around the base's high school, even as everyone else prepares for the big Halloween bash. More the lethal slayer type than a detective, it still doesn't take too long before she and her samurai sword stumble into something.