If you read the manga, some disappointment is in order. Kei is just not that big of an a-hole in the movie. In fact, everyone in the movie has been toned down; they don't seem as despicable as their comic counterparts. Granted, a LOT of elements were taken out, but the overall tone is a more positive one than the nasty, cynical, and dark atmosphere of the comic. However, the film by itself without drawing any comparisons to the comic is satisfactory. A friend who had never heard of Gantz before thought the film felt like a big Twilight Zone episode.