To watch the entire Harry Potter saga in two days is to be overwhelmed by a lot of things. By the 1,179-minute cumulative running time, nearly 20 hours of lessons, broomsticks, and white-knuckle peril. By the sheer weight of wizardly neologism: kneazles and quaffles and bowtruckles, Godric Gryffindor and Horace Slughorn, riddikulus! and reducto! and petrificus totalis! By the parade of wondrous U.K. thespians, cashing checks for 10 years (like Alan Rickman, who’s played Snape in every movie) or breezing by the set for a week’s work (like, in the latest film, Kelly Macdonald, who’s touching and a bit scary as a ghost).

But, mostly, to watch the entire series is to be overwhelmed by the pleasure (and surprise) of seeing a film property made right. Despite some preliminary hiccups, the movies have been handsome, rewarding adaptations of tricky material, pitched perfectly between the often-competing interests of superfans and newbies. In anticipation of the release of Harry Potter and the Deathly Hallows: Part II, I watched all eight of the films in a 48-hour stretch to figure out: Why did this series succeed, for fans and for casual viewers? And what, in the end, is the value of the Harry Potter movies—besides keeping an entire generation of British actors knee-deep in country homes?

Viewed in total, the Harry Potter series rarely sold out the book’s fans to cater to a popular audience—and, more importantly, vice-versa. Sure, there are details in the movies that drive devoted followers of the books mad: talking letters, flying Death Eaters, goblins in HP7B wearing teensy V-neck undershirts. And what about the laughable notion that the Imperius Curse is a sweet-smelling cloud or makes the victim’s eyeballs opaque? The whole point of the Imperius Curse is that you can’t tell a wizard’s been Imperiused! Jeez!

But I digress.

The point is, those little changes—and plenty of big ones, too—were all made in the service of making the movies movies. (Except maybe for the goblin undershirts, which seriously make no sense at all.) And the films have struck an uncanny balance between delivering the moments from the books that fans desperately need to see and finding their own storytelling rhythms. While only one of the films can truly stand alone as the work of an auteur—perhaps predictably, that standout, Alfonso Cuarón’s Prisoner of Azkaban, is the lowest-grossing of the series—they fit together neatly as a unified whole.

The movies made expert use of their young cast, wisely adapting the film characters to match the qualities the three stars offered. Emma Watson’s Hermione is both more glamorous and funnier than the one in the books; Rupert Grint’s Ron sillier and tougher; Daniel Radcliffe’s Harry darker and angrier. That’s not an accident; those are canny choices designed to make the most out of children who, plucked from obscurity before puberty, transformed over the years of filming into entirely different people.

The films’ ever-starker cinematography matched the maturing of its characters and darkening of its subject matter; I’d love to see the artist Brendan Dawes make side-by-side Cinema Redux images of the first film’s fire-lit frames and HP7b’s near black-and-white color scheme. This final film even pays off a silly running gag about a minor character’s propensity for blowing himself up that’s unique to the movies. While viewers who’ve never read the books might be confused at timesby the myriad plot twists and exposition crammed into each film, they’ve never felt cheated—never felt that the movies weren’t for them.

Credit for this achievement goes, as it should, to the directors of the films, the screenwriters, the craftspeople, and of course to J.K. Rowling herself. Considering, though, how often movie fans (and critics) curse the studios and producers who seem unable to make decisions for anything other than the most callow of reasons, it’s worth noting that a great deal of the artistic success of the Harry Potter series comes thanks to Warner Bros. and producer David Heyman, who’ve consistently made surprising—and excellent—decisions.

Perhaps the most important decision of all was who they chose to direct the third film in the series: Cuarón, who, even though his picture underperformed (relatively—I mean, it still made $250 million), jolted the series to life and built a scaffold on which director David Yates could construct the four films he’s made.

Following the second film, Chamber of Secrets, the series was at a crossroads. A lead actor, Richard Harris, passed away after the filming of Chamber, forcing the producers to recast Dumbledore. Financially, that film made $50 million less than its predecessor; artistically, both films were duds. The director Chris Columbus built the world of Hogwarts without delivering real magic. There was never any doubt that the series would continue; of course it would, with so much money to be made. But in which direction would it turn? Would the producers and the studio choose someone who could deliver product just like Columbus? Or would they choose someone who could make a real movie?

Compare the Potter franchise’s situation with that of another Warner property, the Batman series. In 1994, with Tim Burton leaving after Batman Returns, Warners replaced him with Hollywood vet Joel Schumacher. It must have seemed like a safe choice at the time; Schumacher had turned John Grisham’s The Clientinto a nearly $100-million hit, and had a string of solid dramas behind him, from St. Elmo’s Fire to Flatliners. He was a creature of the studio system. The result? Two terrible movies, Batman Forever and Batman and Robin, the latter infamous among Batfans for its benippled Batsuit and generally despised by everyone for its obstreperous stupidity. * It took an indie auteur, Christopher Nolan, to reboot the series 10 years later with Batman Begins.

With Harry, though, Warners didn’t make the safe choice. Alfonso Cuarón had made only a handful of movies, most recently a sexy Mexican comedy-drama, Y Tu Mamá También. He’d never shot anything close to the scale of a Harry Potter. But Azkaban was fantastic: bold, smart, teeming with magical ideas from the very start. The movie opens not with a scene from the book or a beauty shot of Hogwarts but with a moment of the film’s own invention: Harry hidden under his covers at the Dursleys’ house, practicing lumos maximus, his glowing wand illuminating the room. Each time his uncle checks on him, Harry feigns slumber; each time his uncle closes the door, he’s back at it with teenage enthusiasm. It’s a funny bit of business, but it’s also a potent piece of image-making—resonant with the secrecy of Harry’s talents, his excitement about mastering them, and a curious tinge of shame at his 13-year-old lack of control when the spell goes haywire and lights the entire house.

Cuarón made marvelous use of Radcliffe, Watson, and Grint, and populated crucial adult roles with gritty actors Gary Oldman, David Thewlis, and Timothy Spall. He cast Michael Gambon as a younger, sprier replacement Dumbledore. Azkaban was the first of the Potter movies to show a director’s vision walking alongside J.K. Rowling’s, not trailing behind. Suddenly a Harry Potter movie could be something more than a by-the-numbers cash machine. It could be ambitious and creative. The kids could push the storytelling along, not weigh it down. A real director could make something lasting.

Not all of them succeeded; Mike Newell’s Goblet of Fire botched too many great set pieces, and David Yates’s Half-Blood Prince felt overstuffed by half. But without Cuarón’s success, a BBC veteran like Yates probably doesn’t get selected; without Cuarón’s casting bull’s-eyes, Mike Leigh favorites Imelda Staunton and Jim Broadbent might not be playing Umbridge and Slughorn so perfectly.

Most importantly, without Cuarón, it’s hard to imagine Yates would have the freedom to make the Potter movies his own: to make the Ministry of Magic an automated nightmare straight out of Brazil; to shoot action sequences as loud and surprising as gunfights; to let Harry and Hermione dance to Nick Cave, even though it’s not in the books, because it turns out that’s just what the audience needs to see.

“Why are you here? All of you?” Harry asks a quartet of beloved figures from his past near the very end of Harry Potter and the Deathly Hallows: Part II. At a recent screening, the question seemed directed not just to the specters onscreen but at the teary-eyed fans in the audience, for whom the final movie in the series represents one last chance to live in the world J.K. Rowling created—and that Warner Bros. managed, somehow, not to screw up. It didn’t matter whether we were fans of the books, or the movies, or both. And so the answer Harry receives in reply to his question felt like it came from all of us: “We never left.”



Correction, July 14, 2011: This piece originally had the two Batman movies directed by Joel Schumacher in the wrong chronological order. (Return to corrected sentence.)