Sam Harris is quickly becoming one of my favorite modern philosophers to read. In this book he takes on the subject of free will and the notion that it is just an illusion. As usual Sam Harris gets right to the point and shows how we are not the causal agents of our own thoughts, and the implications it has for our us and society. I am sure that this will draw plenty of criticism from others, but it is exactly the kind of thought provoking exploration we need to better understand ourselves; I found it very well argued and it gave me pause for thought on what it means to truly be free.
I highly recommend this one, and since it is a rather short book it will not take up too much of your time.