Dark times await us, Harry. There are no longer kids here; this is the start of the teenage years.
There's no doubt that this is considered the best Harry Potter film, and before, the best book. Not only does it add to the universe, but it also tells a very good story. It's not your average "light-hearted" story. This is a darker story, but not as dark as the later installments.
The film starts off at the Dursleys. Marge Dursley (Pam Ferris), Vernon's older sister, has come to visit and, like the Dursleys, she hates Harry Potter (Daniel Radcliffe). After a terrible "accident," Harry runs off and heads to The Leaky Cauldron, a dark, shabby pub and inn for wizards. While residing there, he reunites with his best friends, Ron and Hermione (Rupert Grint and Emma Watson). As Harry and his friends enter their third year, things aren't as they seem. There's a murderer on the loose who is after Harry. The "murderer" is played by none other than Gary Oldman.
As with each new Harry Potter film, new characters are introduced. This year's additions are Professor Sybil Trelawney (Emma Thompson), whose tea readings don't hold back when she looks into Harry's cup from the bottom and sees death in the leaves, and Professor Lupin (David Thewlis), who instructs Harry in a difficult spell that is supposed to shield him from Sirius's evil magic. We also have a new Dumbledore, played by the late Irish actor Michael Gambon, taking over from Richard Harris, who passed away in 2002.
Besides the cast, we have a new director, Alfonso Cuaron, known for films like "A Little Princess" (1995) and "Y Tu Mama Tambien" (2001). He takes the place of Chris Columbus, the director of the first two films. However, Chris Columbus did remain as a producer.
What makes this film the best? Well, it's simple. Without looking at the technical stuff, The Prisoner of Azkaban tells a very good story, has great character development, great action, a wonderful score by John Williams, and some funny moments. But if one were to look at this from a technical standpoint, the best way I can describe this film is that it's a cinematic masterpiece!
Despite my 4/4 ranking, there are some things I would like to point out that I didn't like in the film. I didn't like Tom the bartender's recasting; it's just for pointless comic relief. The hunchbacked Tom makes Jar Jar Binks seem like a god. I also didn't really like Harry getting his Firebolt at the end of the film. In the book, Harry gets the Firebolt from Sirius before actually meeting him. Professor McGonagall (Maggie Smith) refuses to let him have it because she thinks it might be cursed.
Those are just minor criticisms. Harry Potter and the Prisoner of Azkaban (2004) is still a great film, despite my complaints.