Daniel Radcliffe as Harry Potter in “Harry Potter and the Deathly Hallows: Part 1.” (©Warner Bros/courtesy Everett Co)
You do the math. Alfonso Cuaron’s “Harry Potter and the Prisoner of Azkaban,” which many of us consider the high point of the series, ran 141 minutes.
Perhaps because it took the most liberties with J.K. Rowling’s sacred text, that third film in the series turned out to be the lowest grosser, collecting a mere $795 million worldwide.
Small wonder that Warner Bros. is stretching out Rowling’s final book, “Harry Potter and the Deathly Hallows,” into a pair of movies (the seventh and eighth “HP” films) that may be the most lucrative yet — the first of which runs five minutes longer than “Azkaban.”
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While this is no doubt a solid business decision and may well please devotees who demand extreme fidelity to Rowling’s text, I suspect many of my fellow Muggles will join me in checking their watches at regular intervals during this extremely s-l-o-w movie.
Certainly Emma Watson, who has morphed from a preteen into a gorgeous young woman while playing the brainy Hermione over the course of a decade, gives a performance that at several junctures indicates she’s grown bored with her marathon role.
Even the stalwart Daniel Radcliffe (Harry) and Rupert Grint (Ron) seem very weary from having to go through the motions one last time — albeit with five o’clock shadow.
It’s telling that the movie’s best sequence — The Tale of the Three Brothers, which explains the title — does not even involve the no-longer-child stars.
As its done in animation with cut-out figures, it likely didn’t even require the services of David Yates, the British TV director who helmed the previous two installments in an efficient, anonymous style he demonstrates again here.
Yates utterly bungles the big opening set piece, in which allies are transformed into multiple Harrys as part of an effort to help Harry elude the Snatchers of Lord Voldemort (Ralph Fiennes).
Not much better is an interminable chase sequence set in the Ministry of Magic, where our heavily disguised heroes are trying pluck a Horcrux — one of the keys to Voldemort’s immortality — from the neck of Dolores Umbridge (Imelda Staunton).
Harry’s return to his ruined childhood home — and his parents’ grave — on Christmas Eve is far more effective.
The script by series regular Steven Kloves continues in this dark vein when the trio flees into the woods, and Ron begins to suspect that Hermione prefers Harry to him.
But like practically everything else, it goes on past the point of diminishing returns.
Mostly Yates serves as a traffic cop, introducing glorified cameos by a vast array of distinguished British actors who have little to do but deliver expository bits.
Newcomers Bill Nighy, Rhys Ifans and Peter Mullan join the ever-growing cast of series regulars like Helena Bonham Carter, Robbie Coltrane, Richard Griffiths, Miranda Richardson, Alan Rickman, Timothy Spall, David Thewlis and Julie Walters.
Michael Gambon’s Dumbledore, killed in the last installment, turns up in flashbacks.
Beautifully shot but a soulless cash machine, “Harry Potter and the Deathly Hallows: Part 1” delivers no dramatic payoff, no resolution and not much fun. Hopefully we’ll get that in the final installment next summer.
lou.lumenick@nypost.com