There are more than 700 named characters in the Harry Potter books, so even some major faces had to be left out of the films due to time constraints. While most of the characters important to the plot make repeat appearances throughout the series, there are a few who either merged with other characters or were left out entirely. About a dozen major characters were left out of the film adaptations, plus several whose roles are diminished.
J.K. Rowling builds a complex world in her seven-book series, introducing dozens of characters who are peripheral to the main action. In addition to the throngs of Gryffindors and Slytherins, there are Death Eaters, members of the Order of the Phoenix, Ministry of Magic officials, and a plethora of magical creatures. Some characters only have a scene or two, while others are present throughout the series.
Axing these characters might disappoint fans, but it keeps the movies moving. By focusing on the heart of the story, the film adaptations stay clean and effective. Unfortunately, the absence of some characters also means eliminating their sub- or side-plots. While not essential to the main storyline, these layers enrich the plot and often deepen the suspense. The Harry Potter films tend to favor action over mystery, cutting a lot of the exposition that makes the Wizarding World so complex and engaging.
Peeves
Although there are many ghosts in the Hogwarts castle — including one specifically associated with each house — Peeves the poltergeist is the most omnipresent. The mischief-making ghost can always be counted on to cause trouble for students and teachers alike. Peeves doesn't have an essential role in the plot, but it's a bit odd to see Hogwarts on screen without his screeching presence. Peeves is a thorn in the side of all, taunting students and pulling juvenile pranks. In the first book, he causes trouble for the Golden Trio (Harry, Hermione, and Ron) by alerting caretaker Argus Filch they're breaking curfew. In later books, he spreads rumors about Harry being the heir of Slytherin, reveals Sirius Black has infiltrated the castle, and joins Fred and George Weasley in a campaign of terror against Dolores Umbridge.
Winky
Winky the house elf may not seem like much, but her sporadic appearances in Harry Potter and the Goblet of Fire put the Golden Trio on the trail to uncovering the truth about the Crouch family. Barty Crouch Jr., the culprit responsible for putting Harry Potter's name in the Goblet of Fire and delivering him to Voldemort, almost singlehandedly orchestrates the Dark Lord's return. By leaving Winky out of the film, the writers gloss over much of Crouch Jr.'s backstory and lessen the mystery surrounding the events of Harry Potter's fourth year.
Winky first appears at the Quidditch World Cup where is she is fired by Ministry official Barty Crouch Sr., prompting Hermione to take up a crusade for house-elf rights with S.P.E.W., the Society for the Promotion of Elfish Welfare. Winky later turns up at Hogwarts, falling into depression and dropping a series of cryptic hints about the Crouches. It's eventually revealed that Winky was tasked with caring for Crouch Jr., a convicted Death Eater who was broken out of Azkaban and kept hidden by his father. Winky's absence in the movie creates a lot of questions about Crouch Jr. and the death of Crouch Sr., which is never fully explained. It also eliminates the somewhat problematic storyline exploring house-elf enslavement, which could be good or bad depending on who you ask.
Ludo Bagman
As the organizer of the Triwizard Tournament, it's pretty strange that retired Quidditch player Ludo Bagman is left out of Harry Potter and the Goblet of Fire. In the novel, Bagman serves as Head of Magical Games and Sports, commentating during the Quidditch World Cup and serving as a judge in the Triwizard Tournament. Throughout the contest, Bagman is suspiciously helpful when it comes to Harry, giving him undeserved high scores and offering advice. It turns out he's bet a significant amount of money on Harry's victory, and when the results of the tournament are muddled, Bagman is forced to flee to escape his gambling debts.
One of the parties to whom he owes money is the Weasley twins, who are deeply annoyed Bagman took off before settling his debt. When Harry learns they wanted to use their winnings to open a joke shop, he doesn't hesitate to turn over his Triwizard prize money, 1,000 galleons, so they can live their dream. It's a touching moment that's lost in the movie. Bagman is replaced relatively easily in other areas, but his absence kills some of the story's suspense.
Professor Binns
Professor Binns is another consistent character in Harry Potter whose absence in the films doesn't unduly affect the plot but does make Hogwarts a little less magical. The ghostly History of Magic professor is infamous for giving lectures that put students to sleep. His class is often used as a planning period for the Golden Trio, who ignore him unrepentantly. One significant book moment for Professor Binns comes in Harry Potter and the Chamber of Secrets, when Hermione raises her hand to ask him about the titular chamber. Shaken out of his usual monotone routine, Binns proceeds to give an actual lesson on the myth, piquing students' interest for the first time all year. In the movie, this role is assumed by Professor McGonagall.
Marietta Edgecombe
Ravenclaw student Marietta Edgecombe may not be the most memorable Harry Potter character, but she has an important role in Harry Potter and the Order of Phoenix. In the movie version, Dumbledore's Army is betrayed by Cho Chang, who reveals their whereabouts to Umbridge under the influence of a truth potion. In the books, however, that role falls to Cho's friend Marietta Edgecombe. Marietta is conflicted from the start of the story, and eventually turns over the D.A. under threat from Umbridge. Marietta's betrayal earns her a hex from Hermione that makes zits erupt on her face spelling out the word "Sneak." More importantly, she serves a reminder that, as Dumbledore says, "'We must all face the choice between what is right and what is easy."
Charlie Weasley
Charlie Weasley, the second oldest Weasley child, is mysteriously absent throughout the Harry Potter movies, although he appears in several crucial scenes in the book. Charlie, who works with dragons in Romania, is the go-to guy whenever the Golden Trio are having dragon troubles. During Harry Potter and the Sorcerer's Stone, Charlie helps relocate baby dragon Norbert before Hagrid is caught. Later, Charlie helps wrangle dragons for the first task of Triwizard Tournament, tipping Ron off in advance.
The Portrait of Phineas Nigellus Black
Phineas Nigellus Black, a former Hogwarts headmaster and disgruntled Black ancestor, makes his first appearance as a magical portrait in Harry Potter and the Order of the Phoenix. Phineas is able to travel between his portraits in Dumbeldore's office and 12 Grimmauld Place, the headquarters of the Order of the Phoenix. As such, he's often called upon to pass messages between members of the order. In the fifth book, he alerted Sirius (his great-great-grandson) that Arthur Weasley had been attacked by Nagini.
Phineas takes on a more crucial role during Harry Potter and the Deathly Hallows, helping Snape track down the Golden Trio. His assistance is the only way Snape is able to hand over the Sword of Gryffindor, one of the only weapons capable of destroying a Horcrux. Although he is sometimes unwilling, Phineas' aid shows that not every pure-blood supports Voldemort.
Frank and Alice Longbottom
Frank and Alice Longbottom aren't introduced until Harry Potter and the Order of Phoenix, but their presence looms large over their son Neville throughout the series. As founding members of the order, the Longbottoms fought against Voldemort and eventually fell victim to the Death Eaters. Tortured into insanity by Bellatrix and three others, the Longbottoms were admitted permanently to St. Mungo's Hospital, where Neville regularly visits them and Harry Potter eventually encounters them. Like Harry, Neville Longbottom grew up never knowing his parents and it's their condition that eventually drives him to become a war hero in his own right.
Andromeda and Ted Tonks
Nymphadora Tonks, a somewhat clumsy Auror and Metamorphmagus who can change her appearance at will, quickly became a fan-favorite when she appeared in Harry Potter and the Order of the Phoenix. But fewer people may know of her mother and father, Andromeda and Ted Tonks. Andromeda's unmarried surname was Black – she was one of the three Black sisters, along with Narcissa Malfoy and Bellatrix Lestrange. Like Sirius, she was disowned from the family after she married Ted, a Muggle-born. Andromeda and Ted don't appear often in the books, but they're significant in the later novels when they provide aid to Harry.
Ted is killed in the Second Wizarding War, but his legacy lives on through his grandson Teddy Lupin, the son of Tonks and Remus Lupin. After Tonks and Remus also die in the battle against Voldemort, their son Teddy becomes Harry's godson. Teddy, who appears in the epilogue of Harry Potter and the Deathly Hallows, is also left out of the movies, despite his place in Harry's life.
The Gaunts
In addition to the many living characters in the Harry Potter series, there are some characters who appear only in memories. The Gaunt family is introduced in Harry Potter and the Half-Blood Prince when Dumbledore takes Harry into the Pensieve to better understand Voldemort and his Horcruxes. In one memory, Harry witnesses scenes from the life of Merope Gaunt, Voldmort's mother. Merope, who was abused by her brother Morfin and father Marvolo, fell in love with a rich Muggle nearby, Tom Riddle. She used magic to make him fall in love with her but, a year after their marriage, released him from the enchantment, hoping he would stay regardless. Instead, he left her. Through these memories, it's discovered that two heirlooms of the Gaunt family were made into Horcruxes — a locket that once belonged Salazar Slytherin and the ring of Marvolo Gaunt.
Another important character who appears in memories and anecdotes and omitted from the movies is Ariana Dumbledore. Ariana, introduced in Harry Potter and Deathly Hallows, is mostly discussed in the context of Rita Skeeter's biography of Dumbledore. Later, Dumbledore confesses his sins to Harry, telling him about his younger sister's death. Ariana was killed during a confrontation between Dumbledore, Grindelwald, and Dumbledore's brother Aberforth, a result of his quest for the Deathly Hallows. Much of the story is cut from the final films, although Ariana does appear as a portrait during the Battle of Hogwarts, guarding a secret passage into the Room of Requirement.
Other Notable Characters
Many other Harry Potter characters make only brief appearances in the films, their roles from the books greatly reduced. For example, Gryffindor Lee Jordan, who appears in the first movie as the Quidditch commentator, has a much larger role in the novels. In addition to his unrepentantly biased Quidditch commentary, which appears throughout the series, Jordan is responsible for launching the Potterwatch underground radio service in Deathly Hallows. The pirate radio program, co-hosted by Kingsley Shacklebolt, Remus Lupin, and Fred Weasley, provided some much-needed hope to opponents of Voldemort during the war.
Also left mostly out of the Harry Potter films are Amycus and Alecto Carrow, the Death Eaters responsible for torturing Hogwarts students. The Carrows were named deputies under Severus Snape during Harry Potter and the Death Hallows and were the main targets of Dumbledore's Army, led by Neville Longbottom and Ginny Weasley. They are mostly overlooked in the films, as are some other specific Death Eaters who infiltrated Hogwarts in Half-Blood Prince and fought for Voldemort in Deathly Hallows. While it's understandable that some characters' presence or arcs needed to be cut, it's disappointing that some of those
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