This Trilogy has already made it into my top 10 list. The books follow Azoth/Kylar. As he goes from being a lowly street rat to a powerful wetboy (super assassin) and beyond.
They aren't always easy reading, at times there is too much detail and too many new names, making you feel like you are trying to keep up with the story, but these aren't common enough to be a real negative.
There are awesome twists, amazing action and Brent Weeks (author) isn't afraid to kill off characters, which means you're never sure just who is safe.
A definite read for any fantasy lover… though it is definitely a book for the mature. There are various adult themes at work here: murder, rape, mutilation, torture, betrayal and lots and LOTS of swearing.