Monster.
It's a very awesome psychological thriller and one of the best Anime ever.
http://en.wikipedia.org/wiki/Monster_(manga)
http://www.animenewsnetwork.com/encyclopedia/anime.php?id=3750
Read up and watch the show.
Also Johan the villain is the poster boy of the Complete Monster trope.
http://tvtropes.org/pmwiki/pmwiki.php/Main/CompleteMonster
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Burning Spies is one of my Specialties!