Almost the entire cast of students and teachers return, though some for only a few minutes of screen time. Notably absent is the late Richard Harris, who's Dumbledore was a highlight of the previous films. Michael Gambon wisely provides an entirely new interpretation of the character to great effect. Also missing this time around is John Cleese as Nearly Headless Nick, as well as the entire Gryffindor Quidditch team.

The additions more than make up for any absences. Gary Oldman, in the title role, is nearly unrecognizable as the wild-eyed, manic Sirius Black. Though we don't see him in the flesh until the film's third act, his presence permeates the whole film. Emma Thompson makes the most of her small role as divination professor Sybil Trelawney, delivering an offbeat, comic performance. The real standout, however, is David Thewlis as Professor Lupin. Thewlis' scenes with Radcliffe are without a doubt the best thing about the movie.

Visually, the film is stunning. The effects team seems more comfortable with the massive sets now, allowing their digital handiwork to linger in the background rather than calling attention to itself. The most prominent CGI character is far more realistic than the troll of Sorcerer's Stone or the House Elf of Chamber of Secrets, and the more subtle effects blend almost seamlessly.

While students were always seen in their wizard robes in the prior films, they quite understandably wear jeans and sweatshirts outside of classes here. Small changes such as this one make ground the fantasy of the film in a more solid reality, further removing the flightier, less serious elements of its predecessors.

John William's score is more subdued and more accomplished than his earlier efforts for the franchise. While all of the key themes return at the appropriate moments, its the new music that really stands out, further enhancing the new tone and visual style.

On the whole, this is Cuaron's film through and through. By taking a realistic approach to fantastic material and targeting a more adult audience, the director has made the franchise his own. The new approach to Rowling's work is a welcome one after two trifling attempts by Columbus. Though Cuaron will not be around for the fourth film (Mike Newell has that honor), the incredibly dark and depressing Book Five could be right up his alley.

Harry Potter & The Prisoner of Azkaban is both a continuation of the departure. Fans who enjoyed the first two movies will find more to love here, and those who found them childish will welcome the more serious approach.

Two final recommendations: First, if you have not read the book, be sure to either do so ahead of time or go with someone who can explain it to you afterward. Secondly, if there is an IMAX theater showing the large screen version of the film anywhere near you, see it there. You won't regret it.