Every doll besides 9 and 5 in the film 9. In the original short film, the remaining seven dolls did appear, but only for a few seconds at the end of the film. The feature film takes all of them and gives them larger roles and actual personalities (as well as complete character make-overs).
In Kung Fu Panda, the Furious Five were little more than window-dressing. In Kung Fu Panda 2, they have a much more active role, particularly Tigress. Over the course of the entire series, Mr. Ping, Po's adopted father, goes from a minor character to one of the main protagonists of Kung Fu Panda 3.
In the original Bambi Ronno is an unnamed stag who fights over Faline with Bambi. In the midquel he's a fleshed out buck and the central antagonist of the movie.
In the Tintin comic The Secret of the Unicorn, the minor character Ivan Sakharine is a pushy but ultimately harmless model ship collector who is briefly suspected of stealing Tintin's model of the Unicorn. In the film adaptation of the same comic, however, he is the main villain and the descendant of the pirate Red Rackham. Ironically, in the comic Sakharine is later attacked by the real thief, and if a brief cameo appearance in Red Rackham's Treasure is anything to go by he eventually made his peace with Tintin.
Speaking of which, Tanya got quite a bigger role in Fievel Goes West when compared to the original movie, where she only has a couple of lines and could easily be cut from the story, practically only existing to give Fievel someone to sing his Distant Duet with.
In Rock-A-Doodle, the Grand Duke of Owls is the main antagonist and the cause of all the trouble in the movie. In the play Chanticler by Edmond Rostand, the Grand Duke is only a minor villain - instead, the main villains are the Blackbird and the rival rooster who fights Chanticler. The former receives Adaptational Heroism while the latter is Demoted to Extra.
In the first Toy Story film, Woody and Buzz were the real focus of the film and all the other toys were relatively minor characters. The second film gives much more screen time to Slinky, Rex, Hamm, and Mr. Potato Head. And likewise, Mrs. Potato Head only appeared in the beginning and end of the second film while Barbie was only in one scene roughly past the middle; they both had much bigger roles in the third movie. This also applies to the Little Green Men from the claw machine scene of the first movie. Apparently becoming an Ensemble Dark Horse, they went on to having a signifcantly larger role in the second movie, became recurring characters in Buzz Lightyear of Star Command, and were major characters in the third film even being the Big Damn Heroes.
Jiminy Cricket was originally a nameless cricket who, in the original book, got squashed by Pinocchio in one chapter (and came back as a ghost much later). In the film, he becomes Pinocchio's friend and adviser and has since appeared in countless other Disney projects.
Ariel's sisters from The Little Mermaid get a major role in the third movie, the prequel The Little Mermaid - Ariel's Beginning.
In Zootopia, Finnick has very minimal screen time in the movie. However, there is an implied history between him and Nick Wilde, one of the protagonists, and in the video game, Zootopia Crime Files, he has a supporting role as one of the suspects in a case.
Kanga and Roo were usually the most sparsely seen characters in the original Winnie-the-Pooh animations and even in the New Adventures series, had only a handful of moments in the limelight. Starting from The Tigger Movie Roo started to become a more central character, with Kanga getting more importance from relation. Springtime for Roo and Pooh's Heffalump Movie in particular have Roo as the pseudo-lead. The 2011 movie demotes them back, though even then has Kanga and Roo take part in a lot more humour than before.
So many characters in Star Wars that it would be impossible to list them all. For example, watch the cantina scene from the original film; every last patron has at least a name and a bit of backstory. Some actually get their own story in the anthology book Tales from the Mos Eisley Cantina; several who hadn't been named ended up on the Star Wars Databank, where fans were allowed to come up with their own backstories and names, then vote on which ones were the best. After that, though, they tend to never come up again - the Star Wars Expanded Universe is infamous for this and a few characters do recur, but honestly, most characters in the EU were either named and had a line or two or are original creations who were never on screen. Even fan favorites like Boba Fett and Wedge Antilles, moving on to their own novels and appearing again and again, were minor non-mains who still had lines and plot significance.
Remember that nameless red droid with a bad motivator from Episode 4? This trope was mocked in the non-canon comic Skippy the Jedi Droid, where he was a Force-Sensitive droid who used to work for Jabba. He self-destructed on purpose because he could see the future and knew that R2 needed to go with Luke, or even Skippy's Parody Sue skills couldn't stop Reality from Ensuing badly.
How about, say, the silver protocol droid Threepio meets in Cloud City just before he gets blasted? E-3PO.
A good example of the difference ascension makes: This is a normal Imperial Guard◊. And here's Kir Kanos◊, who wasn't in the films but has a comics plotline of his own, in what could be a case of the job producing an Ascended Extra.
Several characters from Death Star. The guy manning the Death Star's main weapon, who appears once and says "Stand by"? There's a whole story about him.
Wulff Yularen, originally an unnamed background officer on the Death Star in A New Hope was given one in the collectible card game and then generally forgotten. Come 2008 and he's probably the largest Republic non-Jedi, non-clone military figure in Star Wars: The Clone Wars for the first two seasons.
In the novels, Arwen appears only briefly in the main narrative with the majority of her and Aragorn's story relegated to a chapter in the appendix. In Peter Jackson's version, she is featured prominently in all three films and replaces several minor characters, like Glorfindel who aids Aragorn and the Hobbits as they flee the Ringwraiths. Not only does Arwen replace Glorfindel, she's given the additional task of personally carrying Frodo upon her horse, and her Crowning Moment of Awesome — "If you want him, come and claim him!" — is a unique addition to the film. In the novel, Glorfindel places Frodo on his horse and then stays behind with Aragorn and the Hobbits to do what he can to slow the Ringwraiths' pursuit, at which point the narrative focus shifts to Frodo.
Bret McKenzie's bit part as an elf at the Council of Elrond was expanded into a speaking role in the third film purely because of an Internet meme that had sprung up about the character from fans.
In The Hobbit, several characters go through varying levels of this. Azog, The Pale Orc, who had been briefly mentioned (and had never appeared) in the books became the main villain of (at least) the first movie. Radagast, the Brown Wizard, was also promoted from a bare mention to a major, plot-important character, though to a lesser degree than Azog.
Alien introduced The Space Jockey, which was an ominous creature that appeared to be the pilot of the Derelict. It had been killed and fossilized before the events of the first film, and it was at the centre of much speculation among the fandom, as well as many non-canon stories in the EU, for over 30 years before its identity was revealed in Prometheus.
Deborah Myers in Rob Zombie's Halloween is a very literal example, since the character actually was an extra in the original John Carpenter film, appearing in only one scene toward the beginning standing beside her son after he kills his sister, and had no dialogue. In Rob Zombie's reimagening, she was played by the director's wife, was written to be a stripper, and was the secondary character in the whole first act of the film before she kills herself. She also appears in Zombie's sequel in various dream sequences with a white horse, which many viewers took as Zombie's excuse to once again cast his wife in the film.
It happened with other characters too. Judith Myers was hardly an extra in the original film, but she did only appear in one (important) scene before she's killed by her little brother. This happens a bit later in Zombie's film, where she had several scenes. Her boyfriend is also given an expanded appearance, and is even killed. Paul, Annie's boyfriend, is also given a large appearance in the adaptation. In the original film, he only "appeared" as a voice on the phone (voiced by John Carpenter himself). Laurie's parents were also given expanded, more important roles, with her dad appearing in only one scene in the original film, and her mom not appearing at all (though she did turn up in a flashback in the first sequel).
Tommy Doyle in Halloween: The Curse of Michael Myers, where he was the main character (and played by a then-unknown Paul Rudd in his first role). In the original film, he had some screen-time as the kid Laurie was babysitting, but hardly the main character.
Nurse Marion Chambers was a fairly minor unimportant character in the original film, but had a decent supporting role in the first sequel. She turned up again 17 years later in Halloween H20: Twenty Years Later, where she's killed in the opening scene.
The Meganulon (Giant dragonfly-like monsters) from Rodan were only minor characters in the film. Later, they would become the major villains in Godzilla vs. Megaguirus.
Scabior in the Harry Potter and the Deathly Hallows Films. He appears very briefly in the books when he and other snatchers capture the trio and take them to Malfoy Manor. After that, he disappears from the plot, though there is speculation that he is killed by Voldemort after the trio escapes with Dean, Luna, Griphook and Olivander. He appears much more in the films peppered about to the point where he even appears in bits of Part 2 that he didn't appear in during that part of the book.
Captain Billy Cutshaw in The Ninth Configuration. The film is a Stealth Sequel to The Exorcist, and Cutshaw was the astronaut who was confronted by possessed Regan MacNeil and told that he would "die up there." Configuration opens with Cutshaw suffering a nervous breakdown moments before a space flight, resulting in him being committed to a military-run insane asylum.
In The 2005 Movie version, Willy Wonka has a father/dentist named Dr. Wilbur Wonka. He never appeared in the original book nor in the 1971 movie.
Ocean's Eleven: Denny the whale (uber-producer Jerry Weintraub) has a tiny cameo in the first film, causes the second film by unwittingly bragging about the heist to two European master thieves, and makes amends in the last film when he convinces the other big spenders to leave Bank's casino. Also, the mansion seen in the last movie is one of Jerry's Big Fancy Houses.
Playing with this trope, Guy Fleegman in Galaxy Quest was just another Red Shirt who got killed in the original series. But after going on a real space adventure with the crew gets his own starring role in the new Galaxy Quest series.
In The Crow, there's that one little girl whom Eric helps that has a name similar to his dead fiancee's, yeah that one... Well, she gets a name change (Sarah), a big role in the film (the bestest buddy of Shelly and Eric), and her mom's involvement with Funboy is upped. From there, she becomes the love interest in the sequel and once again is in the series.
Agent Phil Coulson is one of the most triumphant examples ever. He started out as a minor comic relief character in the first Iron Man movie. His popularity led to his role becoming recurring in Iron Man 2 and Thor. Then he became the main character of two of the Marvel One-Shots short films. Then he got a role in the Ultimate Spider-Man animated series and became a Canon Immigrant to the main 616 universe in the comics. Then he got a much bigger role in The Avengers, even appearing on some versions of the poster. And now he's Back from the Dead and is starring in his own series. All within five years since his first appearance.
"Happy" Hogan, Tony Stark's bodyguard in Iron Man played by director Jon Favreau, has considerably more lines in the second movie; in addition, he gets to beat down a guard, ram Ivan with his car, and has Black Widow (aka Scarlett Johansson) put him in a headlock with her legs.
Iron Man 2: Jack White was originally hired as the food stylist who prepared and served the salmon carpaccio to Vanko in the aircraft hangar, but he ended up appearing in several scenes as Jack, Hammer's assistant.
In the comics, Peggy Carter is, at best, an important footnote to Steve and his primary love interest, Sharon Carter. In the films, though, she's become one of the most prominent supporting characters, even after Captain America: The First Avenger seemingly concluded any more adventures in the 40s. The first issue of the 2011 Captain America series even uses her death from old age as a jumping-off point specifically because she'd now be familiar to audiences. It's worth noting that the filmmakers have tried to use Peggy in every single (Earth-bound) MCU vehicle after The First Avenger. Joss Whedon wrote a scene for her in The Avengers, and she has cameos in Captain America: The Winter Soldier, Agents of S.H.I.E.L.D., Age of Ultron, and Ant-Man, plus, she took center stage in Agent Carter, which was such a huge hit that it spun off into her own regular TV series.
In the comics, the Iron Legion were an extremely minor group that only appeared in two issues back in the 90's. In the MCU, they have pivotal roles in both Iron Man 3 and Avengers: Age of Ultron.
Hope Van Dyne is an extremely minor character from the comics, and only appeared in the Marvel Comics 2 continuity. In Ant-Man, she's promoted to major character status and is effectively the film's female lead. She becomes the new Wasp in The Stinger, and even gets her name in the title of the sequel.
Likewise, Darren Cross doesn't have the same scale of villainy in the comics as he does as the movie's Big Bad. He's also MUCH cooler looking in the movie.
Hawkeye, the Avenger that got the least amount of screentime in the previous movie, gets a considerably larger role in the sequel. His family is even briefly shown.
J.A.R.V.I.S. in a sense, he ascends from an A.I. created for the MCU to become The Vision.
Dr. Helen Cho. In the comics, she's an extremely minor Posthumous Character, and is only notable for being the mother of Amadeus Cho. Here, she's more fleshed out and takes Phineas Horton's place as the creator of the Vision.
Laura Barton. She was a very minor character in The Ultimates who only appeared in two issues, and is most notable for dying to advanceHawkeye's storyline. She is not only alive in the movie, but has a fairly sizable role and gets some great lines.
Kraglin had barely a handful of lines in Guardians of the Galaxy and accomplished no more than the nameless Ravagers. In Guardians of the Galaxy Vol. 2, he plays an important part in both Taserface's mutiny and Yondu's subsequent escape, and effectively becomes the Guardians's getaway pilot during the fight with Ego. He also has a large role in Yondu's funeral.
Martin Clunes plays a supporting character in Saving Grace, Dr. Martin Bamford. The character was expanded into two prequel tv films explaining his background. Sometime after that, the character was given a retool, and became the main character on the series Doc Martin.
In "The Whisperer in Darkness" by H.P. Lovecraft, George Akeley, Henry Akeley's son, is a very minor character who is only mentioned a couple of times in his father's letters, is never seen in person, and clearly survives the events of the story, as Wilmarth explicitly keeps in contact with him afterward. In the movie based on it, he is a key liason between Henry and Professor Wilmarth early on. Unlike the story, he is strongly implied to be caught and killed offscreen by the Mi-Go when he tries to deliver the Black Stone to Wilmarth.
In the original Rocky, Little Marie appears in one scene where Rocky walks the 12-year-old home. Three decades later, Marie shows up in the sixth film Rocky Balboa as the lead female character and love interest (after Adrian's death).
Ulla in the original film The Producers is nothing but a walking sex joke, barely speaking any English and only showing up to dance occasionally. In the musical, she's made into a fully developed character who speaks English more or less fluently, and becomes Leo's love interest.
In the third movie in the Halloweentown series, Halloweentown High, Ethan (a warlock) was a minor character who was mainly a rival to Marnie but who wasn't important to the story. In Return to Halloweentown, he is a love interest to Marnie. This may be because Lucas Grabeel, who played Ethan, had just been in High School Musical and Disney was trying to promote him.
The Greatest Gift, the short story that inpsired It's a Wonderful Life, says nothing about Mr. Potter other than the fact he owned a photography studio. The movie turns him into a Corrupt Corporate Executive who owns nearly all of the town and seizes a couple opportunities to ruin the protagonist's life..
In the original Dracula novel the Brides only make two appearances and are unimportant side characters. Many of the film adaptions, like Bram Stoker's Dracula orVan Helsing greatly expands their roles, making them Dracula's right hand women and powerful combatants.
Q receives this treatment in a couple of the James Bond movies. While usually he's just there to give Bond his new devices and then takes off, in Octopussy he actually helps Bond when he raids the villain's hideout at the end and travels to Isthmus City to help Bond out in Licence to Kill after 007 goes rogue to get revenge on Sanchez, even ignoring Bond's request that for his own good he should return to London.
Also, M in every other Bond film just gave Bond orders and info on the mission. In Skyfall, she was given a backstory and protecting her was the driving force.
In How the Grinch Stole Christmas! (both the original book and cartoon), Cindy Lou Who is just a character who exists to show that the Grinch is a liar, with only one line. In the movie version, she practically becomes the co-star, playing a more vital role in the plot than any character other than the Grinch himself.
In The Wizard of Oz, the Wicked Witch of the East didn't really even rate as an extra, as she's only seen as a pair of feet sticking out from under Dorothy's house. In Oz: The Great and Powerful, she's the one who initiates all the trouble: murdering the previous king, sending winged baboons against innocent villages, and maliciously tricking her own sister into hating Oscar and becoming the Wicked Witch of the West.
Roadblock isn't exactly one of the leading members of the G.I. Joe team, but plays a big role G.I. Joe: Retaliation.
In The Hangover trilogy, Leslie Chow goes from a minor role in the first, to a bigger supporting role in the second, and the main antagonist in the third.
Pinhead of the Hellraiser series was a minor component in the original novel The Hellbound Heart. Come the film adaption, the more prominent Cenobites from the novel either couldn't speak (Butterball) see or speak (Chatterer) or had their motion limited by their complicated makeup (Female Cenobite). So, Pinhead took the lead, and quickly became the face of the franchise.
The Jason Bourne Series: Nicolette Parsons in Identity started out as a bit of an inexperienced analyst who had subtle ties to Bourne and was on the sidelines for the whole movie. Supremacy had Nicky be the one to attest to the fact that Bourne had amnesia and she allowed for herself to be sent out in the field to meet with him and learned his side of the story as to the deaths of their agents earlier (albeit while being held at gunpoint). Ultimatum had Nicky become the possible new love interest, had Bourne run into her again and team up with her to learn about Blackbriar and expose the conspiracy. In the first movie, Julia Stiles received 10th billing for her role, in the second one, she received 4th billing for her role and in the third one, she was billed only 2nd to Matt Damon.
Subverted with Jason Bourne as she not only goes from 2nd billing to 5th billing in this one (lower than the last two had her), but it readily becomes apparent that she is primarily Back for the Dead.
Back to the Future Part II: Biff Tannen's 1955 gang plays a bigger part than in the first film. In the alternate 1985, it's shown that they're still working with Biff when he's become insanely wealthy, and when Marty is back in 1955, they chase him into the gym where Marty's other self in the first film is playing, and they go backstage to fight "him", so Marty has to stop them in a way that won't impede upon the first film's chain of events.
In the original Sleeping Beauty, King Stefan was just a Bumbling Dad of a king who had only a couple scene. In Maleficent, he's a guileful, skilled warrior who was the titular character's childhood friend, and whose actions are what started the plot of the movie in the first place.
Aurora herself is this. Despite Sleeping Beauty being about her, she lost screentime to the fairies and Maleficent in the first half of the film, and was comatose and mostly absent in the second half. In this film, she's much more active, seeking out the truth of her curse herself, riding off to her father's castle, and has an important role in the final battle.
The Chief Elder of the Community from The Giver is a minor character, but is bumped up to be the Big Bad (as the representation of the totalitarian authority) in 2014's The Giver. To a lesser extent, Asher and Fiona (who just...stop appearing in the narration after a certain point in the book) have far more to do in the film adaptation than they do in the book.
In the animated film, Ella's birth parents were both dead. In this film, they appear onscreen and play more important parts in the introduction.
The Fairy Godmother only appears once in the original film. Here she narrates the film, and appears throughout it disguised as an old woman.
Even the prince qualifies, as he barely had any screen time in the animated film.
Halo: Nightfall: Randall Aiken, a.k.a. Randall-037, existed long before Nightfall was even thought of, having already been mentioned a few times in the Halo novels as being one of the few Spartan-IIs who were genuinely MIAnote To buttress the propaganda that the Spartans were invincible, those that were killed in action were always listed as missing in action instead, and having had a minor on-screen role in the short story Pariah.
Angela who get left behind in Paper Towns during the road trip, gets to go in the film giving her a bit more focus.
The Hunger Games: Seneca Crane, Caesar Flickerman and Claudius Templesmith have a lot more to do, with the movie showing scenes that Katniss is not present for. President Snow also has much more to do than he did in the novel but as the Big Bad of the series, this was necessary.
Effie's role in Mockingjay was a bit part, but with Mockingjay Part 1, her role expanded due to the popularity of Elizabeth Banks' performance.
TRON: Alan's co-worker had one line and was credited as "popcorn guy" because that sole line was asking to eat some of Alan's popcorn. However, since he was played by the same fellow (Dan Shor) as Ensemble Dark Horse Ram, which implied he was Ram's User, he was given a substantial role in the TRON: LegacyFlynn Lives!Alternate Reality Game and publicity materials as Roy Kleinburg, an idealistic and stubborn man who refused to waver in his support of his former bosses, even after the new Encom management fired him.
Although a character in the books and is frequently referenced by other characters, as well as e-mails she sends to WICKED which readers are shown as epilogues to each book, Chancellor Ava Paige never appears in person or has any interaction with the Gladers during the original trilogy note Her one interaction in The Death Cure with Thomas occurs whilst he is unconscious and only able to hear her voice meaning she still only appears off-page. In the films she actually does physically appear on screen, played by Patricia Clarkson, appearing at the end of The Maze Runner (2014) in a video directly addressed to the Gladers where she is killed off, later revealed to have been faked, and in Maze Runner: The Scorch Trials she is present during the climax when WCKD attacks The Right Arm and the surviving Gladers.
Assistant Director Janson a.k.a. "The Rat Man" only appeared in one chapter near the start of The Scorch Trials and didn't appear again until the next book — The Death Cure, where he became the Big Bad. Here he’s promoted to main antagonist status and spends most of the film pursuing the protagonists.
The Scorch Trials briefly featured a Crank nicknamed "Blondie", who appeared briefly to kidnap Thomas and Brenda forcing them to drink hallucinogenic-spiked drinks and party with him and two other Cranks. The film turns the character into Marcus, who the Gladers have been searching for in order to find The Right Arms’ base of operation, which he would know the location of as a former member of said organization. His aforementioned actions from the book are changed from the delusional actions of someone going insane from The Flare virus, to a deliberate ploy to drug, capture and sell Immunes to WCKD.
WarCraft has Durotan be the main character on the orcs' side and makes him instrumental to stopping Gul'dan from bringing the rest of the Horde to Azeroth, while in the game, his biggest claim to fame is fathering famous Horde Warchief Thrall.
The Bishop in Les Misérables (2012), as compared to his role in the musical note But not the book - he is one of the first characters we meet, even before Valjean, and receives several chapters worth of exposition, as befits Victor Hugo's writing. In the musical, he is given one song at the beginning and is never seen again (the book has a scene where Valjean, as Monsieur Le Mayor, receives a letter saying that he has passed away). The film has him appear at the end, as Valjean is dying, replacing Eponine's role in the scene. Eponine is still visible on the barricade in heaven, indicating that she still has her somewhat-happy ending.