Many eyebrows were raised when Warner Bros. entrusted its family-fun cash cow (to the tune of $579 million for the first two films) to Alfonso Cuarón, fresh off the triumph of a frisky Mexican indie that featured a two-boys-one-woman threesome. ''People say, 'How could the director of 'Y Tu Mamá También' be directing 'Harry Potter'?'' says Harry Potter himself, Daniel Radcliffe. ''Well, it almost makes perfect sense: 'Y Tu Mamá' was about teenagers becoming men; 'Harry Potter' 3 is about a boy becoming a teenager.'' Wait: ''Y Tu Mamá'' had themes? We'll have to watch it again!
Cuarón's ''Azkaban'' -- like J.K. Rowling's novel -- marks the deepening of Harry's voice and the darkening of his world. The boy wizard's third term at Hogwarts begins with the news that a rogue wizard (Gary Oldman), convicted of murder and with ties to Potter's past, has escaped from prison and is headed Harry's way. (Quips Oldman: ''I've done so much R-rated work, it's nice to have a job you can show your kids.'') Meanwhile, Hogwarts has a new Defense Against the Dark Arts teacher, Professor Lupin (David Thewlis), who's inspiring in a ''Dead Poets Society'' kinda way but whose, uh, hairy secret will make it hard for Harry and friends to concentrate on homework. There's also a new Professor Dumbledore -- Michael Gambon, taking over for the late Richard Harris -- and an energetic aesthetic notably different from the epic squareness of Cuarón's predecessor, Chris Columbus.
But the new director's most valuable innovation may have been pushing his young actors to dig deeper; he even had them write essays about their characters. What did Radcliffe discover? ''Harry's a very angry person. If I had to guess, I would say he's really into punk rock.''
THE GOOD NEWS A provocative, potentially electrifying makeover.
THE BAD NEWS Any makeover has its risks -- especially one of debatable necessity. Getting it even slightly wrong could cost ''Potter'' some box office magic.