Black ash emits from Rikka and eventually covers the northern half of Japan, turning people into bloodthirsty zombies.

To contain the infection, the government builds a large wall dividing Japan in two, protecting the humans in the south.

The opposing side, led by Justice Minister Osawa, believes the zombies must be wiped out before Japan is overrun.

After crossing the wall, the trio is attacked by someone using decapitated zombie heads as bombs, but a former policeman named Kaito helps them.

Shortly after the group finds No-Name's sister Maya being tortured and fed on by Yasushi in a zombie-infested bar.

During the chase, Kika kills the zombified bar owner, and Taku sacrifices himself to force Yasushi's vehicle over a cliff.

Nishimura took influence from George A. Romero's film Night of the Living Dead which dealt with current events of the day.

Nishimura stated that there was "quite a lot of satire and social criticism in this film...I describe what ensues after the nation splits in two, with humans controlling one half and zombies the other, and the kind of discrimination that would occur within Japan were something severe like this to happen.

[2] The screening of Helldriver at the New York Japan Society in April 2011 was a benefit in aid for the 2011 Tōhoku earthquake and tsunami.

[2] The review went on to say that the film "suffers from the perennial problem with all zombie movies: the creatures have only one way of attacking and the heroes have only one way of killing—which soon becomes repetitive unless there's an interesting story or characters.

"[5] The review went on to praise the make-up in the film, stating that "Nishimura put tender loving care into image and costume design...Even "walk-ons" have distinct facial features and expressions.