The Gantz opens, revealing unusual weaponry and odd suits. The strangers are sent into the city, ordered to kill an alien that roams the streets - and then the carnage begins.

With the small alien dead, the large alien exacts his revenge, slaughtering many with the group. When the creature pursues Kei, the young man quickly discovers that his physical abilities are enhanced by the suit he wears.

Without his suit, Kei finds himself in serious jeopardy when he captures the attention of the Suzuki alien. Nishi ends up in even graver danger when his suit malfunctions at the worst possible time.