I also read the Harry Potter books, so this accounts for my rateing. There is one part of the movie that never happens in the book and isn't needed for the plot. It also could change how the net movie will begin...not a good sign. Then there is a VERY important part that was totally left out that will totally change the net movie. There is a piece of information that Harry and crew need to drive the entire plot of the next two movies. This information is not given to them in this movie. Otherwise I really liked it. It's one of the funniest movies in the whole series. If you don't read or care about the books then this movie is a five.