I Am a Hero (2015) review: The best zombie movie you’ve never seen
I Am a Hero: Quick Verdict
The Verdict: I Am a Hero is criminally underrated. It sits comfortably alongside Train to Busan and Shaun of the Dead as one of the best zombie movies of the last 25 years. The practical effects are gruesome, the action is relentless, and the unique “muscle memory” twist on the undead adds a fresh layer of horror. It runs a little long, but if you love zombie carnage, this is essential viewing.
Details: Director: Shinsuke Satô | Cast: Yô Ôizumi, Kasumi Arimura, Masami Nagasawa | Runtime: 2h 7m | Release Date: April 23, 2016 (Japan)
Best for: Fans of Train to Busan, gore-hounds who love practical effects, and anyone who wants to see what a live-action Dead Rising movie should have looked like.
Worth noting: The zombies retain “muscle memory” of their past lives, which leads to some hilarious and disturbing moments. Also, be prepared for subtitles.
Where to Watch: Rent on VOD / Physical Media.
⭐ Knockout Rating: 4.0 / 5
(Top tier zombie action)
Welcome to Knockout Horror. The zombie genre rose from the dead in the early 2000s thanks to hits like 28 Days Later and Shaun of the Dead, and we have been swimming in undead content ever since. But while everyone knows Train to Busan, one masterpiece seems to slip under the radar. Today we are looking at the criminally underrated J-Horror gem: I Am a Hero (Ai amu a hîrô, 2015).
Table of Contents
A Hero Down On His Luck
I Am a Hero follows manga artist assistant Hideo Suzuki (Yô Ôizumi). Down on his luck and frequently losing himself to elaborate fantasies of wild success and achievement. His career is floundering and his girlfriend is, frankly, sick of his shit. Kicked out of the house, he wanders the streets.
“Director Shinsuke Satô shows no such apprehension. Heads are popped, arms are pulled off, teeth are knocked out. This is a movie that is actually pretty wince inducing.”
Reports of a mystery virus spreading around the population seem to be getting too close to home as his workmates become sick. Little does Hideo realise, things are about to get a whole lot crazier and, this time, it isn’t all in his head.

I’ve actually been meaning to check this movie out for quite awhile but never got round to it. I have mentioned it a fair few times on our sister site, Ranking Horror, where I have touched on quite a lot of zombie content.
It was actually a suggestion from Darren at The Undead Symphony Podcast that prompted me to make I Am a Hero part of my October movie-review-a-day feature. Huge thanks to him for taking the time. Definitely go and check out that podcast if you are fan of all things Zombie related.
Zero to (Maybe) Hero
Based on the Manga, written by Kengo Hanazawa, of the same name, it goes without saying that we already have a pretty established character and story here. The film version does deviate from the source in a number of ways but this is pretty standard for film adapatations.
Hideo is a hapless individual. He has never achieved anything other than a participation trophy for his work. Despite that, deep in his mind, he believes that he can be a hero but has never had a chance to prove it.
That opportunity is thrust on him after an outbreak of a virus which turns the residents of the city into mindless zombies. Somehow, he manages to avoid becoming infected before meeting up with a high school student called Hiromi (Kasumi Arimura).

Together, they begin a harrowing journey to Mt Fuji where they believe the virus can’t survive. This narrative forms the crux of the story. It’s part road trip and part ode to Dawn of the Dead when our protagonists finally make their way to a retail district housed by a group of survivors. For the most part, it’s your standard zombie horror fare coupled with a few laughs.
Hideo isn’t exactly a compelling protagonist and his inability to push past his overwhelming anxiety can make him a frustrating character. It seems as though some of the more interesting elements of the manga have been cut, too. Still, for fans of zombie movies, you will probably feel at least a little comforted by how familiar it all feels. His growth towards the end of the film is quite satisfying, as well.
Guts, Glory, and Great Zombies
Needless to say, the story isn’t where this movie shines, it’s in the action. The city is in absolute chaos and this is one of the areas where I Am a Hero really comes into its own. Much of the carnage takes place practically rather than via CGI. You have cars crashing into each other, people being run over, zombies munching on unsuspecting citizens, and Hideo at the centre of it all trying to escape.
It’s legitimately impressive stuff. Something about the sheer number of extras and practical approach to the action makes it feel so much more impactful and authentic. I Am a Hero retains a level of realism that makes it seem almost feasible. If this were to happen in real life, it would probably look a lot like this.

The infected aren’t just your typical zombies, either. Sure, they love to much on people’s arms and they look fairly standard. But they actually retain some knowledge of who they were before. This causes them to become stuck in a repetitive action that reflects what they did in real life on a day-to-day basis.
One is attempting to continue shopping, for example, another is repeatedly doming himself by trying to Fosbury flop while practicing high jump. Their focus on these tasks is only broken by their overwhelming desire to kill and eat. It’s a fascinating way of adapting an altogether too familiar trope.
Balancing Zany Laughs with Brutal Gore
The comedy, obviously, plays centre stage, too. It’s fairly typical of zany Japanese movies and if you are a fan of that you will feel right at home. I, personally, am so really enjoyed that element of the film. I really appreciated how daring I Am a Hero was when it came to finding a balance between the laughs and violence, as well.
It’s not just a comedy; that’s only one part of it and the laughs frequently take a back seat. It can be occasionally quite deep, is frequently action packed, often fairly touching, and even a little bit sad in parts. It’s actually a pretty damn violent and grotesque film that’s far more graphic than you might think, as well.

Most zom-coms tend to keep these elements to a minimum. Perhaps concerned that too much gore will put off fans who are here for the giggles. Director Shinsuke Satô shows no such apprehension. Heads are popped, arms are pulled off, teeth are knocked out. This is a movie that is actually pretty wince inducing, in parts.
“One is attempting to continue shopping, for example, another is repeatedly doming himself by trying to Fosbury flop while practicing high jump.”
The practical effects look utterly fantastic, as well. I wasn’t a huge fan of the transformation sequences but everything else is absolutely stellar. Special shout-out to the physical performances of some of the actors, too. It’s utterly incredible and always a feature of Japanese horror that feels extremely special.
Dragging Its Feet (Just a Little)
There’s a distinctly video-game like feeling to a lot of the action and violence. Certain scenes are very reminiscent of the zombie game Dead Rising. You have never seen zombie heads popping in such satisfying fashion outside of the Resident Evil games, either. It’s awesome!
There are issues that deserve mention, of course. I am not sure why Shinsuke Satô thought a two hour plus runtime was necessary. It doesn’t exactly drag its feet but it is definitely a bit on the long side of life. The violence might be a bit much for some people, as well. Especially if you are here for the laughs.
Some are probably going to find Hideo difficult to like. He takes a long time to actually develop and, for the most part, feels like a woefully incapable protagonist. He really needed some quicker growth but I guess that is just part of the story arc.
I think viewers who are used to Western horror might find some of the production values a little lacking. This is just a cultural thing, though. Japanese horror rarely has that shiny veneer that Hollywood horror has. It is far more gritty and raw feeling but that adds to the enjoyment, in my opinion.
The Good, The Bad & The Ugly
The Good
- The Gore: The practical effects are absolutely top-tier. Heads pop, limbs fly, and the carnage feels visceral and real.
- The Zombies: The “muscle memory” concept (zombies repeating their daily tasks) is creepy, funny, and unique.
- The Action: It feels like a video game come to life in the best way. The finale is a non-stop adrenaline rush.
- The Tone: It perfectly balances zany Japanese humour with genuinely dark, brutal horror.
The Bad
- The Runtime: At over two hours, it is definitely a bit bloated. It could have easily lost 20 minutes without hurting the story.
- The Protagonist: Hideo is designed to be a “loser,” but his cowardice can be frustrating to watch for the first hour.
The Ugly: There’s a lot of changes from the manga that will probably leave fans of the comic feeling very shortchanged.
Should You Watch I Am a Hero?
Absolutely. If you are a fan of zombie movies, I Am a Hero is mandatory viewing. It brings a fresh energy to a tired genre, combining the fast-paced terror of 28 Days Later with the underdog charm of Shaun of the Dead. The practical effects alone are worth the price of admission. It’s bloody, chaotic, and totally brilliant.
This review was part of our 31 Days of Halloween 2025 Marathon. Check out the full category for more recommendations.
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