It's interesting to note that, of the three Harry Potter novels thus far filmed, the longest on the written page has turned into the shortest on screen. This is a good thing, because it means that the filmmakers are becoming less literal and more cinematic in their adaptations. A flaw of the first two movies, Harry Potter and the Sorcerer's Stone and Harry Potter and the Chamber of Secrets, is that they tried to cram every nuance into the screenplay - an act that had a negative impact upon the films' pacing. For Harry Potter and the Prisoner of Azkaban, script-writer Steve Kloves has pared . Rowling's story to its essence, resulting in a more streamlined motion picture.（）

Although Harry Potter and the Prisoner of Azkaban stands well enough on its own, it has a "middle chapter" feeling. In other words, there's no real beginning or ending. Little is resolved and the film's climax is low-key. The villain of the first two chapters and the overall series, the dreaded Voldemort, is absent. His apparent replacement is Sirius Black (Gary Oldman), although appearances can be deceiving. All of this doesn't make The Prisoner of Azkaban inferior to its predecessors. The appeal is much the same, but the "feel" is a little different. The tone is darker and more claustrophobic. I attribute this to the change in directors. Chris Columbus, who helmed the first two movies, has stepped into the producer's chair, leaving the primary behind-the-camera duties to Alfonso Cuar (who establishes this closer in nature to A Little Princess than Y Tu Mama Tambien).

If there's a theme to The Prisoner of Azkaban, it's "something wicked this way comes." Those lyrics rattle around in the brain even before they make an explicit appearance. There are plenty of candidates for who can fill the "wicked" role: the convicted killer Sirius Black, who apparently is determined to eliminate Harry Potter (Daniel Radcliffe); the vile Dementors, who are pursuing Black and look like Ghosts of Christmas Future; nasty Draco Malfoy (Tom Felton), the school bully; or Professor Snape (Alan Rickman), who dresses in black and sneers most wonderfully. For Harry, now in his third year at Hogwart's School for Witchcraft and Wizardry, it becomes increasingly difficult to tell friend from foe. While there are no questions about his best pals Ron (Rupert Grint) and Hermione (Emma Watson), nor about Headmaster Dumbledore (Michael Gambon), what about the secretive new professor, Lupin (David Thewlis)? Or Sybil Trelawney (Emma Thomspon), who sees ominous things in crystal balls? For Harry, surviving his encounters with Sirius Black and the Dementors means unraveling the truth about whose betrayal of his parents led to their deaths.

There's no question that Cuar has put his stamp on this movie. The return of so many familiar characters will keep viewers comfortable, but the stylistic changes make it seem as if this Harry Potter adventure is taking place in a different universe. The most obvious change is to Hogwarts. Although outwardly the same, the school is photographed and presented in a manner that makes it more ominous and less friendly than in the previous two installments. Wardrobe is another seemingly minor yet significant alteration. Harry, Ron, and Hermione have abandoned the school uniforms that were their standard garb in The Sorcerer's Stone and The Chamber of Secrets. Instead, they dress in "normal" clothing: sweatshirts, jeans, sneakers, etc. This has the effect of making Hogwarts feel more alien than before.

Moments of character development are widely spaced. (That has a lot to do with the deeper cuts made to the source material.) Still, we learn a few things about Harry's background. The Malfoy/Potter feud enters another chapter. And we see the beginnings of a tentative affection between Ron and Hermione. (The two of them exchange glances and hold hands. There's little question where Rowling is going with this relationship, especially considering the predictability of romance in fantasy stories.)

As in all long-running series, there are some comings and goings. Although Kenneth Branagh is not back (nor was it expected that he would return, considering the fate of his character), his ex-wife, Emma Thompson, joins the cast as the eccentric professor of divination. She doesn't have much screen time, but makes an impression. David Thewlis, a solid character actor, is Professor Lupin. As Dumbledore, Michael Gambon replaces the late Richard Harris without missing a beat - some viewers may not even notice the change in actors. The most significant newcomer may be Gary Oldman. It's a tricky role that he handles deftly. Finally, Nearly Headless Nick (John Cleese) didn't just end up on the cutting room floor - he was excised from the screenplay. Since even a little Cleese is better than no Cleese, here's hoping he makes a return in the future.

The lead trio - Daniel Radcliffe, Rupert Grint, and Emma Watson - are growing at about the same rate as their characters. All are likable and recognizable, and the hope is that they will be able to continue in these roles until the series ends. (Re-casting any of the parts mid-stream would be a mistake.) Of the three, Radcliffe is the weakest actor, but Harry Potter isn't the kind of character who demands amazing range. As Luke Skywalker, Mark Hamill wasn't a world-class thespian, but, despite his shortcomings, would anyone have preferred to see him replaced midway through the original Star Wars trilogy?

The recent bankability of fantasy has resulted in a large number of copycat possibilities entering the production pipeline. With both The Lord of the Rings and the Harry Potter movies proving to be solid box-office performers, there's little question that the genre is here to stay. Although Tolkien's story is done, . Rowling's has at least four more installments to go (the final two of which haven't even been published). If the filmmakers continue to keep the quality level high, there will be plenty of pleasurable hours ahead. Harry Potter and the Prisoner of Azkaban proves that a new director with a different perspective can freshen a series that could otherwise resort to stale repetition.