The screen adaptations of the Harry Potter series leave much to be desired—for book fans, anyway. While stuffing their production chock-full of notable names (truly, the movies are a veritable Who’s Who of British cinema), the various directors involved in the project seem to have utterly ignored the characters who made the books so popular in the first place. Some leeway should, of course, be granted to the many child actors involved in the project, who were cast too young to be sure of their eventual appearance and acting ability (although the latter turned out not to be a problem, especially for the three principals). But what may continue to baffle the most committed Harry Potter fans is the egregious and prevalent miscasting of adult characters, who frequently failed to achieve verisimilitude with their book counterparts.

Adaptation relies on strong casting; if the Harry Potter movies did not quite satisfy book readers, much of their failing can be attributed to misguided casting choices. So many of the characters in the Harry Potter movies do not look like their book counterparts—but the worst characters are those who, moreover, do not act like their book counterparts. It is one thing for directors to disregard minor details when they believe a better performer will enhance a character, but it is a much different thing to cast someone whose entire look and acting style is ill-fitted to the role, as in the worst casting choices of Harry Potter.

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Alastor “Mad-Eye” Moody (Brendan Gleeson)

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Setting aside appearance for a moment, Mad-Eye Moody is one of the most difficult Harry Potter characters to interpret—not least because during his most significant arc, when he teaches Defense Against the Dark Arts in Harry Potter and the Goblet of Fire, he is not actually Mad-Eye Moody. Yet therein lies the brilliance of the character: the manipulative charade of Barty Crouch Jr. both enhances Moody’s formidable aspect and justifies his paranoia. There is a duality to Mad-Eye: he is both venerated as a Dark Wizard hunter and ridiculous in his inability to let go of the sense of danger that served him as an Auror (“Constant vigilance!”).

Unfortunately, the movie adaptation leaned much too hard on the second aspect of the character, allowing his ridiculousness to undermine the respect he has rightfully earned—a hyperbole which is represented quite literally by the strap holding his magical eye in place, turning a key symbol into a confusing steampunk anachronism (perhaps some of the effects budget could have been redirected from the pointless dragon task in the Triwizard Tournament).

Bellatrix Lestrange (Helena Bonham Carter)

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Bellatrix Lestrange is the first lieutenant of Lord Voldemort, but she is his equal in every measure of malice—just as cruel, just as heartless, just as convinced of her own superiority to other wizards (not to mention muggles, for whom she shares the Dark Lord’s utter disregard). Despite her irredeemable actions, however, she is also kind of cool: her hauteur is established immediately and repeated frequently, and it is an essential aspect of how she behaves throughout the books. Her composure only breaks in direct proximity to her master—whom she treats with a breathless, slavering reverence—or in moments where she does not have control (which are rare, for Bellatrix is extremely calculating). Otherwise, she is a model of composure, which only deepens her villainy in the reader’s mind.

Helena Bonham Carter is no stranger to depicting either devotion or villainy—indeed, her iconic portrayal of Sweeney Todd’s Mrs. Lovett includes elements of both. Nor is she incapable of portraying arrogant elitism, as her subsequent role in The Crown attested. Well, then, may audiences wonder why her performance as Bellatrix eschews these aspects of the character in favor of madness. In the movies, Bellatrix Lestrange’s eminent depravity has been boiled down to one trait (a trait which is in only implied in the books)—Bellatrix is crazy. Well might book fans roll their eyes as they watch Bellatrix dance unnecessarily through a fiery cornfield, robbed of the refinement that actually made her so scary as a villain, flattened into a caricature of fantasy antagonism.

Sirius Black (Gary Oldman)

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Ah, Sirius. Teen girls everywhere knew what the Harry Potter casting directors did not: that even the hopelessness of Azkaban prison could not entirely erode the handsome features of James Potter’s former best friend and Harry’s godfather, Sirius Black. Sirius is still in his early thirties when he enters the scene, in Harry Potter and the Prisoner of Azkaban—not yet middle-aged, and not wholly dispossessed of the charisma that made him a memorable student during his time at Hogwarts.

Yet the movie chose an actor more than a decade his senior to portray Sirius, leaning heavily on the character’s role as a father figure to Harry, forgetting that, in the books, Sirius still has a youthful spirit (even immature, in his recklessness and occasional petulance)—more of an older brother than substitute dad. Gary Oldman looks and acts, literally, like an Old Man, when compared with the character he was cast to play.

Severus Snape (Alan Rickman)

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The Harry Potter movies were already being released before most readers knew or suspected what role Snape would eventually play; leading up to that revelation, he was characterized as a snake—as serpent-like as the de facto mascot of Slytherin House (of which he is Head). Much of this characterization is achieved through descriptions of Snape’s voice, which is always calm, low, and smooth—Snape is the perfect spy because he is understated and slippery…and always in control of himself.

Alan Rickman was a wonderful actor with an illustrious career, but one of his defining characteristics was his voice—a trait that he shared with Snape, although the two voices could not be more different. Rickman spoke with a full-bodied, throaty tone, producing a sound that was always resonant, as if his words had already begun to echo within his mouth before issuing forth. Moreover, as an actor, he excelled at displaying complex emotions, rather than masking them. He was an incredible talent—but he could not be more different than Severus Snape.

Albus Dumbledore (Michael Gambon)

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Richard Harris was, of course, a wonderful Dumbledore—there can be no doubt that he would have continued to excel, if not for his untimely death. What fans got next was a Dumbledore who yells; there is no better way to sum up the disparity between Michael Gambon’s performance and the character of Dumbledore than to highlight the discrepancy in volume.

The real Albus Dumbledore would never second-guess Harry when he says he did not put his name in the Goblet of Fire; the real Albus Dumbledore would be a bastion of reassuring equilibrium, minimizing drama and maximizing Harry’s trust (and, by extension, the audience’s). Dumbledore needs that trust—from both Harry and the audience—because it is the only way to move the story forward in Deathly Hallows, after he is no longer there to guide Harry directly. An untrustworthy Dumbledore is, therefore, an ineffective one, undeserving of the confidence that the story places in him.

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