The new "Harry Potter and the Half-Blood Prince" resolves a couple of mysteries, like how Voldemort invades Hogwarts, and how he attacks some of Harry's key allies.

It also resolves an even more puzzling mystery: how the franchise could be permitted to drag on this long without providing employment to Jim Broadbent, one of his country's best actors yet one of the few Brits yet to receive a Warner Bros. cheque.

Broadbent finally gets his Potter dividend here, filling the key role of Professor Horace Slughorn, returning to Hogwarts Magic Academy to mentor Harry, much as he once doted on a protege named Thomas Riddle, who grew up to be the evil Lord Voldemort.

Slughorn, to his shame, imparted some key piece of dark magic to young Voldemort, and Dumbledore (Michael Gambon) assigns Harry to find out what it was.

That movie takes its sweet time getting there, with ample asides devoted to the teen love lives of Harry, Ron and Hermione, but that's fine. Actors Daniel Radcliffe, Rupert Grint and Emma Watson are older and better, and we don't mind spending so much down time with their characters.

Watson and Radcliffe have learned from Grint a knack for light comedy, which "Half-Blood Prince" deploys in subplots about their romantic difficulties. Hermione is angry that another girl has a crush on Ron, who in turn is put off by his own sister's crush on Harry, etc.

It's good fun, and it helps vary the pitch of the 2-hour movie, which would otherwise be bogged down in uniformly dark subplots of infiltration and assassination.

Who will do the dark lord's bidding? This I cannot reveal, but I can reveal that perpetually angry Potta hater Draco Malfoy (Tom Felton) stalks about Hogwarts in all-black Armani, with his blond hair slicked back in a hedge-fund manager hairdo.

Harry, meanwhile, is positioned more as an everyman here, his status as chosen one notwithstanding. He ditches the robe for Chuck Taylors, jeans and a zippered sweater, like an extra in "Superbad."

And he doesn't spend so much time whining about his folks or holding the throbbing scar on his forehead, the symbol of his psychic pain. Here, Harry seems more focused on the well-being of his friends and, as chosen ones go, that makes him easier to tolerate.

Hogwarts on the whole seems a more pleasant place, but maybe I just have a soft spot for a community wherein there are no laptops, no Internet and no BlackBerries, where everybody gets their news from the same yellowed newspaper.

A magical place indeed. *

Produced by David Heyman, David Barron, directed by David Yates, written by Steve Kloves, music by Nicholas Hooper, distributed by Warner Bros.