Gantz (Japanese: ガンツ, Hepburn: Gantsu) is a Japanese manga series written and illustrated by Hiroya Oku. Gantz tells the story of Kei Kurono and Masaru Kato, both whom died in a train accident and become part of a semi-posthumous "game" in which they and several other recently deceased people are forced to hunt down and kill aliens armed with a handful of futuristic items, equipment, and weaponry.