Mischief has finally been managed with this one!

Rating: 10/10 (28 May 2016)

Harry Potter and the Prisoner Of Azkaban is a stunning shift for the franchise's structure and longevity. While The Chamber Of Secrets kept the aesthetic of the first but improved upon it with additions to the aesthetic, the Prisoner of Azkaban decided to make the successfully prestigious choice of continuing that trend but on a more extreme level and in a way that has since lasted with each installment after in the franchise, most definitely for the better.
This shift in aesthetic is simple: only keep the new parts of the aesthetic of the previous entry and add more. Chamber barely did this, keeping the adventurous tone of the previous entry but raising the stakes and featuring more of the Wizarding World's involvement as a whole. Thus, keeping the new parts, Azkaban features the Wizarding World as a whole and the high stakes, but adds the menace and frightful tone of the enemies. This starts the trend of making each film a hybrid of the film before it and the film after it, which works to make each film transition the series further away from the lighthearted start and closer to the dark, Gothic ending without the shift feeling too abrupt.
Most notably, this film feels like the first film where we truly see the Wizarding World as a whole, something that was missing from the earlier two films. Yes, the magic was introduced and magic as a whole was explained and explored, but not this world it existed in or the culture around it very much. The early films were very isolated to just Hogwartz and some alley, not showing us very much of the Wizarding World in the scheme of things.
This movie is the best at enriching the fictional universe without a doubt, really accomplishing some great world-building while not suffering from the flaw of the first film which had the world-building so present it overshadowed the main plot of the film.
In fact, this is one of the most compelling of the narratives that plague Harry each year. We feel so much genuine suspense and tension, something that was distinctly not present at all in the threat of the first film, again as it hardly paid any attention to its main plot, and was not really ever accomplished with the second film because every time the villain tried to do something sinister he was thwarted in doing so, never able to impress his power upon the audience as a result. Here, Sirius is built up perfectly. Mentioning actual things he did, rather than just being told he's bad and so we should be afraid of him. There was no terror in this series so great as being told that all that was left of the man he destroyed was a finger.
This series has been imprisoned by its own lack of confidence until this entry and thus it played it safe, giving us two good films. But now we have a great one, and thus the prisoner that is this franchise has finally escaped.