It's really good, it builds a universe where a lot has already happened. It's set in the year 10,000 and something, which is a lot further in the future than just about every sci-fi story dares go. To me it's the best sci-fi book ever written, but I'm no librarian. The movies really don't do it justice because they aren't long enough to describe the details of every character and society -- there's a 4 hour version of the 1984 movie that was really good though. There was also a TV series, and also one for Children of Dune. The desperation for water is never really gone into in the movies either. They talk about it, but the book conveys it much better.