Harry Potter and the Prisoner of Azkaban (PG) The Day After Tomorrow (12A)

Enchantment and magic - but who made the story disappear?

Few series in cinema history can have had the continuity of the Harry Potter films. Each one features the same actors playing the same heroes having similar adventures in the same settings, so you probably already know whether or not you want to see the new one. Still, this time there have been some changes. Michael Gambon, with an accent that goes on a tour of the British isles, takes over from the late Richard Harris as Dumbledore. And there are yet more of Britain's leading thespians on the cast list, including Gary Oldman, David Thewlis, Emma Thompson and Timothy Spall.

Few series in cinema history can have had the continuity of the Harry Potter films. Each one features the same actors playing the same heroes having similar adventures in the same settings, so you probably already know whether or not you want to see the new one. Still, this time there have been some changes. Michael Gambon, with an accent that goes on a tour of the British isles, takes over from the late Richard Harris as Dumbledore. And there are yet more of Britain's leading thespians on the cast list, including Gary Oldman, David Thewlis, Emma Thompson and Timothy Spall.

A bigger difference is that Harry Potter and the Prisoner of Azkaban (PG) has a new director. Having delineated the world of JK Rowling's novels so efficiently in the first two films, Chris Columbus passes the wand to Alfonso Cuarón, and the maker of Y tu mamá también introduces the one ingredient that the other films were short of: the magic. The early scenes in Privet Drive and Diagon Alley are bejewelled with spooky sight gags worthy of The Addams Family, and Hogwarts has more creaks and shadows than it used to, but Cuarón's best trick is to conjure magic not just from the supernatural, but from the natural. Much of the movie's enchantment derives from shots, filmed in Glen Coe, of lakes and mountains and sunlight on bracken.

Unfortunately, Cuarón concentrates so intently on HPATPOA's atmosphere that he literally loses the plot, and so the one great moment when everything clicks into place and you realise that there wasn't a scene or a character that wasn't essential to Rowling's story - that moment doesn't arrive. The editors have cut so much vital information that the central mystery is still a mystery at the end. It makes for a flawed, frustrating film. But if there's a fuller version to come on DVD it could be a masterpiece.

When the DVD of The Day After Tomorrow (12A) comes out, you might want to fast-forward through any parts that don't involve mass destruction. It's the latest film from Roland Emmerich, the man who pulverised the White House in Independence Day and the Chrysler Building in Godzilla, and now he's hammering most of Los Angeles and New York. The authorities have ignored the warnings of top climatologist Dennis Quaid, and their environmentally unfriendly ways have resulted in an extremely unfriendly environment: cue typhoons, tidal waves, and brass-monkey temperature drops.

Emmerich delivers several outstanding sequences - among them a frightening ice storm in Tokyo and the unnerving progress of an ocean liner through the flooded streets of Manhattan. But he has to fill the gaps between the cataclysmic set pieces somehow, and he tries to do so without the aid of a plot: at no point does Jeff Goldblum pop up and twitch his way through a plan to save the planet.

Of the film's two heroes, all Jake Gyllenhaal has to do is stay indoors, wrap up warm, and pluck up the courage to ask out his lovely classmate; all Quaid has to do is ponder the importance of spending quality time with his family, and then hike through the snow for absolutely no reason other than to facilitate a cool, Planet of the Apes-apeing shot of the Statue of Liberty with frostbite. Bring on the killer hailstones!

n.barber@independent.co.uk