Nakatsu was laid off at his company and now works part-time at a convenience store. One day, Nakatsu forms a vigilante group to protect his town with Toshida, who has a mysterious physical ability, Kanari, who is a female high school student with excellent information gathering abilities, and Kusaki, who wields hammers under his sleeves. As they punish evil doers, the group gains popular support and flourish.
Unfortunately the movie Maniac Hero is not yet available on HBO Max.
| Directing | Keisuke Toyoshima | Director |
| Writing | Shigeyuki Fukumitsu | Original Story |
| Writing | Jun Tsugita | Screenplay |
| Writing | Shigeyuki Fukumitsu | Comic Book |
| Production | Kenichi Yoshida | Producer |
| Production | Tomoo Fukatsu | Producer |
| Camera | Hajime Kanda | Director of Photography |
| Sound | Hiroshi Ishigai | Sound Recordist |
| Editing | Masaki Murakami | Editor |
| Production | Yoshiki Terashima | Producer |
| Sound | Gabriele Roberto | Original Music Composer |
| Sound | Hiroshi Ishigai | Sound |
| Sound | Akihiko Okase | Sound Effects |
| Art | Hidefumi Hanatani | Production Design |
| Crew | Saori Masuko | Script |
