The individual ingredients --- teen angst, existential dilemma, sexual anxiety, purgatory, alien hunting, graphic violence, and computerized spheres that house omnipotent but catatonic men --- could have calamitously collided. In fact, they could have made a grim, clumsy train wreck, like the one that launches the mind-bending, viscerally charged narrative of this fabled manga. But in the hands of Hiroya Oku, writer and digital artist, Gantz is one of the genre’s most thoroughly addictive, eminently readable entries.

The story follows sometimes friends Kei and Masaru on their surrealistic, supernaturally amped adventures through Tokyo, following a train accident that may or may not have killed them. In the realm of the undead, the less-than-dynamic duo --- typical teens: angry, disenfranchised, mischievous, and constantly thinking of sex --- is drawn into an underbelly of alien-hunting by a mysterious orb named Gantz, who apparently controls their destiny and promises to restore their quote-unquote real lives once they have completed enough missions for him. These missions (think Mission: Impossible meets The Matrix) come replete with high danger, cool gadgets, hyper-gory violence, and Big Bads named Onion Alien, Bird Alien, and Buddhist Temple Alien.

New characters join Kei and Masaru. The female ones frequently shed their clothing. The males are quick to slice, dice, and otherwise draw blood. The series succeeds --- over nearly 500 issues --- by offering consistently inventive individual missions against the ongoing mystery of who and what is Gantz and what is the purpose of these body-splattering, alien-hunting assignments.

Gantz is front-loaded with metaphysical queries (a la "Lost"), a hardboiled sensibility (a la Hammet or, say, Haruki Murakami), and graphic ultra-violence (think M-rated first-person shooter games, the ones where decapitations and downpours of blood are the norm), and is, resultantly, an awful lot of fun. Grim fun, but fun.

The utter normalcy of Oku’s teen characters makes their upstream paddling against their environment’s endlessly enigmatic sci-fi shadings all the more delicious, while the writer’s willingness to wrestle with recent historical atrocities adds a deft and deep --- if oftentimes delirious --- resonance to the storyline. Oku’s artwork, digitally rendered, is breathtaking, even though it’s often incredibly grisly --- one that’s decidedly not for the faint of heart.