Last month, Harry Potter and the Cursed Child premiered in print and on stage, picking up where we last left Harry Potter, as a middle-aged dad sending his son Albus off to school (Hogwarts, of course) for the first time. Earlier this week, J.K. Rowling announced she’ll be releasing Pottermore Presents, a trio of e-books that promise to delve further into the “dark side” of the wizarding world. One person likely celebrating that news is Dave Thier, who in 2011, lauded the ways the films embraced the dark melodrama that the books merely dabbled in. That, Thier writes, is how the movies succeeded more so than the books. “The Harry Potter books were not built on Rowling’s ability to craft a narrative,” he wrote. “They were built on her ability to craft a world.” As more parts of the Harry Potter story come into play, it will be interesting to see if that still holds true — or if things only get darker from here. Perhaps it’s best to prepare your Lumos charms now.

Seven years ago, the Harry Potter series seemed like it was going to be hard to put on screen. Rowling’s books were long, endlessly complicated, and full of things like butterbeer, grindylows, fizzing whizbees, and boggarts.

But early reviews of the eighth and final installation of the Harry Potter series are in, and the word is that director David Yates and his cast have managed a task with near impossible expectations, to the tune of a 96 percent on Rotten Tomatoes. It looks like the new movie, like the rest in the series, hasn’t just managed to yank a couple more million out of some blockbuster novels. It’s been able to take the Harry Potter story and turn it into the epic Rowling couldn’t manage.

It's rare that the movie actually fixes problems from the book, but in this case the simplicity and narrative drive of a Hollywood script was just what the series called for.

The basic story in Harry Potter is an old one, and a good one. The boy of destiny is plucked from ordinary circumstances and becomes incredulous when he’s told the truth behind his real identity. Some training, trials, and a crisis of self-confidence later, he emerges as the true hero ready to defeat ultimate evil.

But the Harry Potter books were not built on Rowling’s ability to craft a narrative. They were built on her ability to craft a world. The most memorable moments were never plot developments, but rather things like the introduction of Hogsmeade, the Quidditch World Cup, or the first reveal of Diagon Alley.

Rowling’s writing had that endlessly obsessive quality required of a true world builder, but her storytelling couldn’t stack up to her setting. With every book from three on, she talked about how the stories were getting “darker.” But while “darker” things happened—some characters died, terrible monsters appeared, and schoolyard quarrels evolved into wars of racial purification—the tone could never quite catch up to the circumstances.

Take a passage from towards the beginning of the Deathly Hallows, Harry is trying to convince his aunt and uncle about the mortal peril they’ve found themselves in. But when “Daedalus Diggle,” the wizard meant to protect them arrives, they find a “small man in a mauve tophat … sweeping the floor in a deep bow,” and announcing himself in a “squeaky excited voice.”

Silliness butts up against severity throughout the latter books. As the main characters are preparing to infiltrate a government intent on racial cleansing, they do so with the aid of "puking pastilles." As Xenophilius Lovegoodreveals the wand that could be used to kill villain Lord Voldemort, Rowling constantly dashes to the side to describe "erumpent horns," "crumple-horned snorkacks," and "freshwater plimpies."

It isn’t that playfulness has no place even in the grandest of stories, but Rowling’s world of pointy hats, nosebleed nougat, and Latin-language shouting had a hard time supporting the weight she tried to place in it—as a result, she resorted to writing much of Deathly Hallows with caps lock on.

The characters followed suit. The curiously loquacious Voldemort could never summon the sort of pure evil of Lord of the Rings' Sauron or Star Wars' Emperor Palpatine. He says things like “Kill his friends—the more the better,” with the air of a petulant bully. Ultimately, he’s defeated by a trick of ownership over the elder wand—hardly a fitting end for a “dark lord.” Harry himself remained stuck in the whiny, adolescent act two of his story, storming away from the Order of the Phoenix because he can’t come to terms with being important. He defeats Voldemort, but he never matures into the hero his story demanded he be. There was an epic to be told, but Rowling was never able to get past the appropriately childish tone of her earlier books and commit to the gravity of the classic story she had set out to tell.

Then they made them into movies. Hollywood knows nothing better than the old stories, and the boy of destiny is a favorite: We’ve seen it everywhere from Star Wars to Rookie of the Year to The Matrix. Rowling seemed somehow resistant to telling that story directly, but the movies have shown no such trepidation. And they’ve given the tale the kind of narrative drive and attention to tone that the books lacked.

Maybe most importantly, the movies have actors. A character like Voldemort was able to adopt the dangerous, reptilian strength that he deserved in the hands ofRalph Fiennes. Warner Bros took a bold move making eight movies in ten years, but it paid off. Harry had to mature, because Daniel Radcliffe grew up with the films.

The novels still gave the movies plenty of weirdness to grapple with. In The Deathly Hallows: Part 1, the characters, true to the book, sat in the woods doing more or less nothing for half the movie. And the strange narrative trick that was the eleventh hour introduction of the Deathly Hallows still robs the finale of its ability to move with the full weight of the series behind it. But the pacing, tone and drama of Deathly Hallows: Part 1 felt so much closer to the epic closer that a seven-part story on Potter's scale set out to have. Many critics say that's the case as well with Part 2. It’s rare that the movie actually fixes problems from the book—but in this case, the simplicity and narrative drive of a Hollywood script was just what the series called for.

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