In May of last year I posted about the Percy Jackson books. Last week the movie of the first book the "Lightning Thief" came out. I took our two kids and the two kids we carpool with. Our 9-year-old has read the first book in the series, and the older boy we carpool with has read all 5 and did so voraciously.
I think all of the kids liked the movie, but the older boy and I spent most of it comparing it to the book. There were a ton of changes. The kids are supposed to be 4-5 years older than in the book (16 vs 12, and the lead actress was actually 23.) The plot was changed pretty heavily, and they pulled the Hydra out of book 2 and put it in this movie. They skipped the St Louis Arch and a ton of other stuff. The biggest change was that the underlying villain was completely missing. In the books, the person behind all of the plot was the Titan Kronos, father of the gods. In the movie, the plotter was a demigod son of Hermes. If they plan on making another movie, they are gonna have to get Kronos into the plot somehow. Considering the books center on Kronos's return to power, it would be hard to make the movies without dealing with him sooner or later.
I listened to an interview with the author. He sold the movie rights before his book even got published and had almost nothing to do with the movie. He hadn't seen it yet at the time of the interview--he's been working on his new "Kane Chronicles" book and the first of the new "Camp Half Blood" books (Percy Jackson sequels, of a sort,) so he hasn't had time to see it. His two sons had seen it though and seemed to like it.
I thought the movie was okay and I'm glad it's holding its own at the box office this week. I hope it does very well.