Perfect action movie to watch: you don't need context at all, start the movie even if you don't know anything about Gantz, everything important is explained. It looks beautiful, the monsters are unique and the weapons too, and many epic battles, truly a good Cgi experience, the creative team behind this movie is really good as a whole they did a very serious job, everything feels realistic (except maybe the women chests) you can really feel the effort of the characters to carry/hit/throw things and their pain when they take damage. One bad thing about this movie is that I don't recommend making "unreceptive" people watchit because it has oversexualized characters.