There, he's joined by his friends and fellow students Ron Weasley (RUPERT GRINT) and Hermione Granger (EMMA WATSON), and sees the school's regulars, such as the friendly groundskeeper, Rubeus Hagrid (ROBBIE COLTRANE), rival student Draco Malfoy (TOM FELTON) and the stern Professor Snape (ALAN RICKMAN).

New to the school are professors Sybil Trelawney (EMMA THOMPSON) and Professor Lupin (DAVID THEWLIS), who has taken over the leadership role of Defense of the Arts. Harry will need his help as he's learned that murderer Sirius Black (GARY OLDMAN) has escaped from the Azkaban prison. Supposedly responsible for the deaths of Harry's parents, it's reported that he's making his way toward Hogwarts and is after Harry.

With Azkaban's ghoulish and dangerous Dementor sentries patrolling the school's perimeter, Harry learns new things about his past as he and the others prepare for Black's arrival.

For many actresses, the latter unfortunately means being over the age of 30, while those in certain franchises eventually outgrow the roles or at least the desired and/or accepted ages of those they play. That's happened many times before (and is rumored to be in the works again) in the James Bond series. While it hasn't happened yet with the "Harry Potter" cast, it's undoubtedly on their and the studio's minds.

After all, while the kids in the books also age, those playing them are doing so at a faster rate, and that will only continue as the film series tries to keep up with the beloved books. It's yet to be a huge deal in the previous films or the third entry, "Harry Potter and the Prisoner of Azkaban," but when you compare the performers now and then, there's a substantial difference in their appearances.

That also holds true for both this effort and the person behind the camera. Replacing Chris Columbus is Alfonso Cuarón who last helmed the sexually charged "Y Tu Mama Tambien." That might seem like an odd fit, but one must remember that he also directed the far tamer and more sedate "A Little Princess." Cuarón does bring a new visual look and feel to the film -- which has both good and bad points depending on how you viewed the first installments -- and it's decidedly more grown-up than the previous entries.

That's not meant to imply that the film is racy, however. After all, the kids are still barely in brief flirt mode (noted when Ron and Hermione grab each other's hands in worry and then quickly let go when they realize what they're doing). Instead, the film's tone and themes are more in tune with teen angst than the more childish and whimsical shenanigans found in the earlier efforts.

Yet, Cuarón apparently hasn't been given complete free rein to revamp the series any way he wants. Although he reportedly truncated the source material (thankfully getting the running time down to around 140 minutes, shaving 20 some from its predecessor), it seems he's been instructed not to forget to appease the series fans.

Accordingly, there are moments and material straight from the first two films, along with the to-be-expected return of characters and their rote interaction with each other. At other times, however, the film feels completely new and fresh, breaking away from the formula that drove the first efforts to financial success. I doubt, however, that any change will have any detrimental impact in such regards.

The result is an effort that occasionally feels at war with itself. I suppose it will thus play better to a wider audience, but I only wished that some of the older material were jettisoned in favor of the newer and improved moments.

For instance, during the film's first hour, I kept writing in my notes that nothing was really happening. Sure, the main plot thrust -- that Sirius Black has escaped from prison and is now coming after Harry -- is introduced, and most everyone from the first films is reunited. Yet, despite the presence of all of the fun if minute magical details of the school -- that have lost a bit of their novelty the third time around -- there just isn't that much plot in the first half. Despite some effectively creepy moments now and then, there's barely enough to keep non-fans interested and/or involved.

Thankfully, things do pick up in the second half when the plot finally gets around to moving forward and the second half of the title subject finally makes his appearance. I have no idea how faithful returning screenwriter Steven Kloves ("Wonder Boys," "Flesh and Bone") is with J.K. Rowling's original material, but at least it finally becomes more engaging.

That's not to say that more astute viewers won't see various developments coming before they arrive and the overall werewolf and time travel angles don't really add anything to the mix (as both feel re-treaded from other films and literary works).

Nevertheless, the performances -- especially from the kids -- are better in this outing. Beyond looking more grown-up, Daniel Radcliffe brings more credibility and depth to the part. Emma Watson and Rupert Grint also fare better this third time around.

Maggie Smith ("Divine Secrets of the Ya-Ya Sisterhood," "Gosford Park"), Robbie Coltrane ("The World is Not Enough," "Message in a Bottle"), Tom Felton ("Anna and the King," "The Borrowers") and Alan Rickman ("Love Actually," "Die Hard") also reprise their respective roles, but aren't afforded the same sort of new growth (although Rickman is still a delight, particularly with his delivery of certain lines). Meanwhile, Michael Gambon ("Sylvia," "Open Range") replaces the late Richard Harris in the role of Professor Dumbledore without much fanfare.

New additions to the cast include Emma Thompson ("Love Actually," "Primary Colors") in something of a comic relief role playing a hippie-type, fortune teller professor, David Thewlis ("Timeline," "Seven Years in Tibet") as Harry's new instructor and ally, and Gary Oldman ("Hannibal," "The Contender") playing the escaped prisoner. All are fine in their roles, but none made any sort of lasting impression on me.

That pretty much sums up the film as well. Visually appealing (with terrific production values) but rather boring in the first half, the film does get better as it progresses. Even so, the directorial dichotomy -- appeasing the fans with regurgitated moments and appealing to others with the decidedly new and improved look and feel -- results in a mixed bag of cinematic offerings.

Moodier, deeper and darker than its more whimsical and adventurous predecessors, "Harry Potter and Prisoner of Azkaban" has its moments and makes one hope that the transition over to the new approach will be complete next time around. It would also be nice if the kids return since, after all, the roles are theirs.

Interestingly enough, I wasn't that impressed while sitting through the film, but have grown to like it a bit more in the intervening days. I'm not sure if that feeling would hold if I saw it again, but it's enough of an improved response to warrant a rating of 6.5 out of 10.