Gantz

Kei Kurono and his childhood friend Masaru Katou die beneath a train after trying to save a man who fell onto the tracks. Yet death does not take them where they expect. They awaken in a sealed apartment with other people who have recently died and a huge black sphere called Gantz, which equips them with strange suits and weapons before ordering them to hunt beings hidden among the city.

The missions offer almost no explanation and even less mercy. Kei is forced to confront violence, fear, and the selfish instincts he once took for granted while trying to understand what Gantz wants from them. Surviving one death has only placed him inside a game where dying again may be final.