This is the third movie in the franchise, and it's the darkest one yet. We're introduced to Dementors, vile creatures who are tasked to guard the prison of Azkaban. When Voldemort disciple Sirius Black escapes, Dementors are assigned to guard Hogwarts putting Harry and his friends in danger.

The introduction of Dementors ushers in a new darker chapter in the franchise. These CGI creatures look every bit the evil creatures they're suppose to be. Accomplished director Alfonso Cuarón shows his great skills in creating tension and atmosphere. Even the darken corridors of Hogwarts are more foreboding. Without spoilers, I also must praise Hermione's part of the plot. The story loops created are usually fraught with problems. This one is done with care, and works great. Looking back, the change in tone is what drew me into the Harry Potter franchise. It is the first great Harry Potter movie and in my opinion, the best of the lot.

The third HARRY POTTER film (still gotta get round to reading the books) and definitely a step in a different direction, with more unpredictable narrative – thank god Harry doesn't have to fight a clichéd monster at the end – and better direction by Mexican Alfonso Cuaron, who makes it look darker, gloomier and more magical. It's just as great as the last two (if not better – I think this is my favourite of the three) and despite the over-lengthy running time, the interest doesn't let up.

Things I noticed in this film were improved acting all around and plenty more humour than in the last two, but thankfully the humour is actually funny for a change. Hats off to Rupert Grint's Ron, the most hilarious character on screen and a wonderful acting performance. Seeing how the kids have grown up is a little alarming, however! Things are pretty unpredictable, with Harry fighting off the monstrous (and excellent CGI-animated) Dementors, wraith-like ghosts which literally suck your face off. Meanwhile there are all sorts of new and weird things happening, like Pam Ferris turning into a balloon and books that bite your fingers off, pretty much like the Luggage from Pratchett's DISCWORLD series.

Added in for good measure are some excellent bonding scenes, tons of humour, a little romance here and there, and some wonderful new creatures animated by computer. The hippogriff and the werewolf, in particular, are fine. The returning actors are fantastic as ever and newcomers Gary Oldman and David Thewlis are very good indeed, although the former a little underused. Thewlis puts in his best turn yet I reckon. Enough action, hijinks, cool effects, and twists (including a little time travel thrown in for good measure) to last any film fan. Here's looking forward to the next one!

This is certainly darker than the first two instalments, and not as funny. But based upon a truly excellent but complex book, it is a very good film nonetheless. In my reviews on the first two films, I forgot to mention the music by John Williams. In all three movies, it is very good, but not Williams's best work. His scores to Star Wars, ET and Home Alone are better. The only real quibble i had with the movie was Michael Gambon as Dumbledore. Richard Harris, the first and better Dumbledore, had died, and although Gambon was good, Harris suited the character a lot more in terms of looks and sincerity. The three leads are still likable, and they are given solid support by Maggie Smith, Alan Rickman and Robbie Coltrane. The real treat lies in the newcomers though, namely David Thewlis as Lupin, Emma Thompson as Trelawney and Gary Oldman as Sirius. Timothy Spall I felt was a little odd for Wormtail. The Dementors I felt quite terrifying, a lot more chilling than they were in the book. All in all, very good. 8/10. Bethany Cox