Gantz Manga Vol. 1: What to Know Before You Read

What Is the Gantz Manga Vol. 1 About?

The short version: Two high school students die in a subway accident. Instead of staying dead, they wake up in a mysterious Tokyo apartment with a giant black sphere. The sphere — called Gantz — gives them weapons, suits, and a target. Hunt the alien. Kill it. Or die again, this time for real.

That’s the hook of Hiroya Oku’s Gantz, a seinen manga — meaning it’s aimed at adult men and features more mature content than series targeting younger readers — that ran from 2000 to 2013. Vol. 1 collects chapters 1 through 11 and covers the first half of the series’ opening story arc (a multi-chapter storyline): the Onion Alien Mission.

The two leads are Kei Kurono and Masaru Kato, former childhood friends who reunite at the worst possible moment — on a subway platform, seconds before a man falls onto the tracks. What happens next sets the entire series in motion.

A few things to know about the tone right away:

• Kurono is not a hero. He’s self-centered, apathetic, and reluctant. Oku deliberately makes him unlikable at the start. This is not a story about a brave protagonist rising to the occasion — at least not yet.
• The world is bleak. The opening chapters deal with bystander apathy, the randomness of death, and the meaninglessness characters feel about their own lives. It’s heavy stuff.
• The violence is graphic. Alien combat in Gantz is messy, detailed, and unflinching. The subway death scene alone sets the bar.

Genre-wise, Gantz sits at the intersection of sci-fi, action, dark fantasy, and horror. It’s often compared to Battle Royale — a Japanese story about students forced into deadly survival games — for its life-or-death premise and morally gray characters, though the alien-hunting angle takes Gantz in a very different direction.

Vol. 1 ends mid-arc — the Onion Alien mission isn’t resolved until Vol. 2. So fair warning: you’re going to want the next volume ready.

Chapters Included in Volume 1

Gantz Vol. 1 contains chapters 1 through 11. Here’s a quick, spoiler-light breakdown so you know the shape of what you’re getting:

• Chapter 1 — “An Incident”: Kurono’s ordinary, disaffected life. The subway platform. The moment everything changes.
• Chapter 2 — “The Black Sphere”: Kurono and Kato wake up in the Gantz apartment. They’re not alone — other recently dead people are there too.
• Chapter 3 — “It’s the Beginning”: Gantz activates. The sphere displays a target, hands out equipment, and the mission begins whether anyone is ready or not.
• Chapter 4 — “Living in the Crevices”: The group is teleported to a residential area. The alien they’re hunting isn’t what anyone expected.
• Chapter 5 — “OK”: First real encounter with the Onion Alien. Chaos ensues.
• Chapter 6 — “It’s Over”: The group scrambles to deal with the alien. Some fight. Most panic.
• Chapter 7 — “They’re Not Human”: The reality of the situation sinks in. The aliens are more dangerous — and more sympathetic — than expected.
• Chapter 8 — “I’ve Done It”: Combat intensifies. The Gantz weapons start to make more sense. So does the scoring system.
• Chapter 9 — “Shall I Kill Them?”: Moral lines blur. Kurono and Kato react very differently to what’s happening.
• Chapter 10 — “A Perfect Score”: The mission continues to escalate. More about the Gantz scoring system is revealed.
• Chapter 11 — “A Meaningless Thing”: The volume ends mid-mission, with the Onion Alien arc far from resolved.

Important note: This volume covers roughly the first half of the Onion Alien Mission arc, which spans chapters 1 through 20. Vol. 2 completes it. If you’re picking up Vol. 1, plan on grabbing Vol. 2 as well — the story doesn’t have a satisfying stopping point here.

Key Characters Introduced

Vol. 1 introduces the core cast that drives the early part of the series. Here’s who you’ll meet:

Kei Kurono

The protagonist — and deliberately not a likable one. Kurono is a high school student who’s apathetic, selfish, and mainly concerned with himself. When he and Kato encounter a man who’s fallen onto the subway tracks, Kurono’s first instinct is to walk away.

This is intentional on Oku’s part. Kurono starts at rock bottom morally, which gives him somewhere to grow. But in Vol. 1, he’s mostly cowardly and self-serving. If you’re used to manga protagonists who are brave and kind from page one — the type you’d find in series aimed at younger readers — Kurono will be a shock.

Masaru Kato

Kurono’s childhood friend and his polar opposite. Kato is brave, compassionate, and driven by a genuine desire to help people. He’s the one who jumps down to help the man on the tracks — and he’s the reason Kurono ends up on those tracks too.

Kato serves as the moral compass of the early series. Where Kurono freezes or runs, Kato acts. Their dynamic — and the tension between their very different approaches to the Gantz game — is one of the best things about Vol. 1.

The Other Gantz Room Participants

Several other recently-dead people appear in the Gantz apartment alongside Kurono and Kato. They include a mix of ordinary people — some panicked, some aggressive, some in total denial about what’s happening. Most are introduced without much backstory in Vol. 1, serving more as a group dynamic than as individual characters at this stage.

The Gantz Sphere

Gantz itself functions almost like a character. The black sphere sits in the center of the apartment, displays cryptic information about targets, provides weapons and suits, and seems to be running the entire operation — but with zero explanation of who made it, why it exists, or what the rules really are.

It’s creepy, it’s fascinating, and the mystery of what Gantz actually is becomes one of the series’ biggest ongoing questions.

The Onion Alien (Negi Seijin)

The target of the first mission. “Negi” means “green onion” in Japanese, which gives you a sense of the alien’s unusual design. The Onion Alien looks humanoid but distinctly alien, and its design — along with the design of its child — adds an unsettling layer of moral complexity. This isn’t a clear-cut “kill the monster” scenario. The aliens have their own lives, and the ethical implications of hunting them are part of what makes Gantz compelling from the very first arc.

Content Warnings — What to Expect

This is important, especially if you’re newer to manga or picking this up based on a recommendation without much context.

Gantz is rated 18+ by Dark Horse Comics. That rating is earned.

Here’s what you’ll encounter in Vol. 1:

• Graphic violence: The subway death scene is visceral. Alien combat involves detailed gore — bodies come apart, injuries are drawn in full. Oku’s art is hyper-detailed and realistic, which makes the violence hit harder than more stylized manga.
• Nudity and sexual content: Vol. 1 contains nudity. The series as a whole has significant sexual content that increases in later volumes. This is present from early on.
• Dark themes: Death, nihilism, bystander apathy, and the meaninglessness of life are front and center. The opening chapters specifically deal with the question of whether anyone would risk their own life to help a stranger — and the answer, for most characters, is no.
• Morally uncomfortable situations: The alien hunt raises ethical questions that the manga doesn’t resolve neatly. You’re watching people kill beings that may not deserve it, directed by a sphere that offers no justification.

For comparison: If you’ve read Tokyo Ghoul or Attack on Titan — both are considered mature manga with violence and dark themes, but neither features explicit sexual content — Gantz is significantly more explicit than either in terms of both violence and nudity. If those series were at the edge of your comfort zone, Gantz will likely cross it. And if you haven’t read those titles, just know that Gantz is among the most intense manga in terms of adult content. It holds nothing back.

Who should be cautious: Anyone sensitive to detailed depictions of death, nudity, or nihilistic tone. This manga does not ease you in — the first chapter opens with the subway incident, and the intensity stays high.

This isn’t meant to scare anyone off. Gantz is a fantastic manga for the right reader. But knowing what you’re getting into matters, and too many reviews gloss over this.

Single Volume vs. Omnibus — Which Edition to Buy

Dark Horse Comics publishes Gantz in two formats. An omnibus edition collects multiple volumes into one larger book — in this case, three volumes in one. Here’s how the two formats compare:

Feature	Single Volume	Omnibus
Contents	Vol. 1 only (chapters 1–11)	Vols. 1–3 (chapters 1–34)
Page count	~236 pages	672 pages
Price	~$13.99	$24.99
Cost per page	~$0.059	~$0.039
Size	Standard manga size (~5″ x 7.5″)	Standard manga size (~5″ x 7.5″)
Publisher	Dark Horse Comics	Dark Horse Comics

The omnibus is the better deal if you’re fairly sure you’ll keep reading. At $24.99 for three volumes’ worth of content (672 pages), you’re paying significantly less per page than buying singles. The omnibus also collects the entire Onion Alien arc plus the beginning of the next arc, so you won’t be left mid-mission the way the single Vol. 1 leaves you.

The single volume makes sense if you genuinely aren’t sure whether Gantz is for you and want to spend less upfront to test the waters. Given the content warnings above, this is a perfectly reasonable approach.

Digital availability: Gantz is also available digitally through platforms like ComiXology and the Dark Horse digital store. If you prefer reading on a tablet or want to try a chapter or two before committing to physical copies, digital is a solid low-risk option.

One practical note on availability: The individual single volumes can be harder to find for later entries in the series, as some have gone in and out of print. The omnibus editions are more reliably stocked. If you end up wanting to collect the full 37-volume series, the omnibus format (which covers the series in roughly 12 omnibus volumes) will be easier to complete.

Where Gantz Vol. 1 Fits in the Full Series

Gantz ran for 37 volumes in total, published chapter-by-chapter in the Japanese manga magazine Young Jump from 2000 to 2013. The series is completed — no waiting for new chapters.

Vol. 1 is the very beginning. Here’s a spoiler-free look at how the series is structured:

Reading Order

Straightforward: Vol. 1 through Vol. 37, in order. There are no side stories, prequels, or alternate timelines you need to worry about for the main series.

How the Story Grows

The series moves through a progression of alien-hunting missions — each one a multi-chapter storyline — that get increasingly complex and high-stakes:

• Onion Alien Mission (Vols. 1–2) — Where it all begins. This is what Vol. 1 covers.
• Tanaka Alien Mission (Vols. 2–4) — The stakes escalate. Characters start to understand the rules.
• Buddhist Temple Alien Mission (Vols. 4–8) — A major turning point for the series in terms of scale and danger.
• Later missions continue to expand the scope dramatically, but listing them here would spoil the progression.

The important thing to know: the series starts small and personal, then gradually opens up into something much, much bigger. If you enjoy Vol. 1 but find it limited in scope, know that the scope expands enormously.

Spin-Offs (After Finishing the Main Series)

Once you’ve finished all 37 volumes, there are two spin-off series worth knowing about:

• Gantz:G — 3 volumes, completed. A separate story set in the same universe with a different cast.
• Gantz:E — Written by Hiroya Oku and Tomohito Ohsaki, with art by Jin Kagetsu. A period-era spin-off set in the Gantz universe. Serialization moved from Weekly Young Jump (ended Dec. 2023) to the YanJan! app. No official English-language license confirmed as of 2025.

Both are optional and best saved for after the main series.

Gantz Anime vs. Manga — Should You Read or Watch First?

There’s a Gantz anime, and you might be wondering whether to start there instead. Here’s the short version: start with the manga. But here’s why:

The Anime (2004)

• 26 episodes covering roughly Vols. 1 through 8 of the manga (the first two major missions)
• Has an anime-original ending — meaning the show’s conclusion was created specifically for the anime and doesn’t match the manga’s story
• The manga continues for another 26 volumes beyond where the anime stops
• The manga’s art is one of its greatest strengths — Oku’s hyper-detailed style is stunning on the page, and much of that visual detail is lost in the anime adaptation

The CGI Film: Gantz:O (2016)

• A standalone computer-animated film adapting the Osaka mission, which takes place much later in the manga (around Vols. 23–27)
• Visually impressive but will reveal major plot points if you haven’t read that far
• If you’ve already seen Gantz:O before picking up the manga, don’t worry — knowing about the Osaka mission doesn’t ruin the experience of reading from Vol. 1. It just changes how you get there.

The Recommendation

Read the manga first. It’s the complete story from start to finish, the art is remarkable, and the anime only covers about 22% of the full series (roughly 8 of 37 volumes). The anime works fine as a supplement afterward, but the manga is the definitive version.

Is Gantz Vol. 1 Worth Reading?

Let’s wrap this up honestly.

What Works

• The premise is incredible. Die, wake up in a room, hunt aliens or die again. It’s a hook that grabs hard and raises immediate questions: Who made Gantz? Why these people? What are the aliens? The mystery engine is powerful.
• Oku’s art is stunning. Even in Vol. 1, the level of detail in environments, character designs, and action sequences is remarkable. This is a visually beautiful manga, even when what it’s depicting is horrifying.
• The characters feel real in uncomfortable ways. Kurono’s selfishness, the bystanders’ apathy, the panic of people thrust into an impossible situation — it all rings true. Oku isn’t interested in heroic idealism. He’s interested in how people actually behave under pressure.
• The moral complexity is there from chapter one. The Onion Alien isn’t a mindless monster. The hunters aren’t noble warriors. Everything is gray, and Vol. 1 establishes that immediately.

What Might Not Work for Everyone

• Pacing in the early chapters is deliberate. The first few chapters spend significant time on Kurono’s mundane life and the subway incident before the Gantz premise kicks in. It’s purposeful world-building, but if you’re expecting immediate action, it takes a few chapters to get there.
• Kurono is hard to root for. This is by design, but it’s still a barrier for some readers. If you need to like your protagonist from the start, Vol. 1 will test your patience.
• The shock value is real. Gantz doesn’t shy away from intense content, and some readers feel the early volumes lean into shock for its own sake. The balance between meaningful darkness and gratuitous content is something each reader has to judge for themselves.
• Vol. 1 ends mid-arc. You’ll need Vol. 2 to see the Onion Alien mission through. This isn’t a complete story unit on its own.

The Bottom Line

Buy if: You enjoy dark, violent sci-fi with morally complex characters and a mystery that unfolds over dozens of volumes. Fans of survival-game stories, alien horror, or manga like Berserk (dark medieval fantasy), Dorohedoro (surreal dystopian action), or Deadman Wonderland (death-game horror) will find a lot to love here.

Skip if: Graphic violence, nudity, or a nihilistic tone are dealbreakers for you. There’s no shame in that — this manga goes hard, and it’s not for everyone.

Gantz Vol. 1 is a strong, provocative start to one of the most unique sci-fi manga out there. It’s not perfect — the pacing requires patience, and the protagonist actively pushes you away — but the premise is so compelling and the art so striking that it earns every page.

If the premise sounds even slightly interesting to you, grab Vol. 1 and see for yourself. You’ll know within a few chapters whether this is your kind of manga. And if it is? You’ve got 37 volumes of wild, escalating, beautifully drawn chaos ahead of you.