Graelwyn, I wholeheartedly recommend Death Note. It has been already recommended, but in passing. Basically, Death Note is a crime thriller manga with a supernatural twist. It is about a bored young genius high school student called Light Yagami, who comes across a notebook that, if you write someone's name in it, they die. Turns out that the notebook was dropped by a bored shinigami (god of death, or grim reaper) called Ryuk in order to provoke something interesting. Light decides to start killing off criminals and cleanse the world of evil, and the public call him 'Kira'. All very well, until the enigmatic L, supposed to be the greatest detective of all time, declares to Kira that he will find out who he is and capture him. Light and L prove to be well-matched opponents, as well as how far they will go: L uses a death-row inmate as a proxy in his first declaration against Kira, and Light unhesitatingly uses the Death Note to murder someone who might be a threat to him, even though he doesn't know that it is a criminal he is killing, and not L.
Although I've spoiled the first couple of chapters, it goes on for a whopping 108 chapters (12 books) of a cat and mouse game with supernatural overtones. It's very dark, but it is also a thoughtful story that raises (even though it wasn't the author's intent) serious questions about morality and power. Discussing too much about Death Note pretty much has spoilers inherent in the process. But it is very good, Graelwyn. Try it.
_________________
(No longer a mod)
On sabbatical...