Though Half-Blood Prince did not stay completely true to the book, the movie did a fantastic job of including important scenes necessary to the plot. It is difficult to accurately portray a 700 page book in 2 1/2 hours and Yates does it well. The cast seemed to really grow up and come into their own in their acting. I was really impressed with Harry, Ron, and Hermione imparticular. Snape and Slughorn were absolutely incredible in this movie as well. I thought the movie wasn't perfect, ,but it was great.