The Mistborn Series: Books Two and Three by Brandon Sanderson

Out of the sheer exhaustion of my mind due to the reading of these two books I have decided to clump them together and to omit summaries of what they are about (they are continuations of the series anyways). If you want to figure out all of the secrets from the first book (not to mention the undermining of everything you thought you knew), then reading these books is a must. I have never read a book/series that has thrown so many surprises around before (I know I said that about The Emperor's Edge series, but the surprises in these two books easily top those). Anyways, the books are incredible. The characters continue to develop throughout the books quite believably and several new characters are introduced. I personally felt overwhelmed by the huge number of surprising events but I thought the books were enjoyable nonetheless. There is a fourth book, but the first three pretty wrap up the story very nicely (except for a bit of a hint dropped at the end about a discovery that still hasn't been made). I'd say that if you've read the first book and liked it well enough, you'd be missing out not to read these as well if only to have everything you thought you knew turned upside down and become something totally different.