I thought they did a really good job with casting & the special effects were great - Grover & Chiron looked great & the Fury, Hydra etc. were pretty convincing as well. In my opinion they could have done a better job with the story line & kept more to the book. Alot of characters were left out & there were some holes if they're planning on making the sequels into movies. My husband & son were really disappointed. Bottom line: don't expect too much & you'll enjoy it; the movie is never as good as the book.