This is the prototype of the cynical anti-hero of the 70s: a bleak post-apocalyptic world, fast action sequences, and a strange metaphorical scenery. Written in 1968, this foreshadows Escape from New York, Mad Max and all those urban violence movies of the 70s and early 80s. As a story, it's a little drawn-out, but stylistically this is as good as it gets.