What's The Most Bleak And Misanthropic Series Of All Time?

Plenty of science fiction and fantasy series have dark themes or gritty settings — but they still offer plenty of hope for the human condition here and there. But what's the most misanthropic series, with the grimmest view of human nature, you've ever come across?

Please include a book cover, photo, poster or clip for your chosen series. And please mention the name, and why it's so dire. Thanks!

Top image: The Walking Dead.