The mascot from the confused.com adverts has had her bust size increased and animated, and her waist made smaller. This is what she looked like originally. Then she looked like this. The latest June 2012 drivers advert (pause at 0:19) shows her with normal legs instead of the black sticks she originally had.
Miranda from D.Gray-Man has an in-universe reason for this, since she originally looked like a ragged old woman, with heavy bags under eyes and a giant mess. At the time she was trapped in a "Groundhog Day" Loop, not to mention that she was dealing with some serious self-worth issues, and after the arc is over and Allen and Lenalee help her out with both, it shows that Miranda really doesn't look all that bad after all. Once she was upgraded to a recurring character, she was redesigned to look more gothic than old. In one one-off drawing, she's even part of fanservice.
Naruto: Before Gaara was rather mean and scary-looking because, well, he was mean and scary. After his Heel-Face Turn, he's been redesigned to look still gothic but much gentler (again, because he generally is).
Takatsuki from Wandering Son, manga to anime. His goofy facial expressions from the manga where changed to better looking ones in the anime adaptation. In the manga itself, due to Art Evolution certain characters such as Doi, Seya, and Mako became cuter and more attractive over time; though it's justified since they're getting older.
The entire cast of Genshiken has had this happen to them, Madarame in particular has benefitted.
Vegeta in Dragon Ball was originally shorter and thinner, and his face was considerably "pointier" than his current look. This was even more noticeable during the anime's original broadcast in the US, wherein halfway through the Namek arc, FUNimation took over the dub, resulting in every character having a new voice, Vegeta included.
Area 88: Compare the way Mickey looks in the first issue of the manga to the way he looks a few issues later. He looks much more youthful in later issues.
Juvia of Fairy Tail was not really ugly at her introduction, but she may have been the closest thing the series had to an average-looking girl, or she could even be considered Flawed Average on the Sliding Scale of Beauty because of her narrow eyes with small pupils and big visble lips. She always had a gloomy expression due to having a Power Incontinence that prevented her from talking to other people. When she lost this "incontinence", she actually started smiling and soon after did a Heel-Face Turn. Due to Art Evolution, her narrow eyes widened and became prettier, and the writer seems to have forgotten that her lips used be that visible. Nowadays, she is definitely one of the best-looking Fairy Tail girls and still relatively unique-looking considering the Only Six Faces tendency for the girls.
Senritsu/Melody in Hunter × Hunter started off grotesquely deformed but eventually became Ugly Cute (with a drastically different design). Reasons for this is unknown, but the change in appearance seems to coincide with her proving herself an ally to the main characters.
Albert Heinrich/004 in Cyborg009 started out much stranger-looking than simply having Monochromatic Eyes and a Glasgow Grin-level mouth; his early appearances had him sporting an unflattering bowl-cut hairstyle that gave his head a very mushroom-like cast, his nose was elongated and pointy (but still only second to 002's Gag Nose), and his facial structure amounted to mostly being a long narrow jawline. Ishinomori gradually drew him more normalized over the course of the manga with the ensuing Art Evolution, to the point where he looked rather handsome in the final chapters of the manga.
A majority of the characters from YuYu Hakusho, mostly the ones who aren't meant to look too attractive in the first place. The attractive ones are all consistently drawn.
Marrow started as a creepy-looking girl who had craggy bones growing out all over her body, but after her Heel-Face Turn, slowly became just an attractive girl with some cosmetic-looking bone attachments. An accident which involved an exploding card, a trip through the astral plane and an alien healing device made her pretty. Then Weapon X performed an experimental procedure on her to give her greater control over her powers that also happened to make her "beautiful" (their words). After she fell off the map completely, she somehow defaulted to somewhere between her "just about to join the X-Men" look and her "alien healing device" look.
From the same team, Nightcrawler's original source of angst was being fairly demonic looking in a superstitious Ruritanian hometown. When he first appeared in X-Men he was short and more "cute" than anything. When he was moved to Excalibur, Alan Davis purposefully drew him standing at six feet tall and modeled his facial features and personality after Errol Flynn. Sure, he was still a blue elf but he was noticeably more charming than his earlier Dave Cockrum incarnation. Other artists have followed suit for the most part.
Even under Cockrum's art run, Kurt was often written as some flavor of Adorkable, Badass Adorable, and even Chick Magnet, so it wasn't a completely out of the, er, blue development.
He even had his own in-universe stuffed doll of himself, the BAMF doll. In the X-Mail letter column, they printed a few letters from people who desperately wanted one!
Callisto was the leader of the Morlocks, a group of mutants with extreme physical mutations. Callisto never looked nearly as inhuman as the others as was best describable as 'butch' and was implied to be living with them less due to her appearance and more due to bad experiences with people. Due to the actions of fellow Morlock Masque, she is transformed into a pretty woman ... and many years later she's altered to have tentacles of varying length and thickness in the place of arms. She at once becomes prettier and more Morlockishly inhuman.
Skin from Generation X. He was explicitly shown and stated to be ugly in his first appearances, but by the end of the series, he was looking positively suave. This has an in-universe explanation, since before the series started he was shown to be able to influence his appearance by concentrating, but doing it too much would give him migraines. Later in the series it is pointed out that his appearance has been improving because he has been learning to control his powers. He can never do anything about the unnatural gray color of his skin, but by issue 50 or even earlier it is no longer hanging off him freakishly while he is conscious.
Rogue originally started out as a rather homely, "butch" looking woman and a member of the Brotherhood of Evil Mutants. After her Heel-Face Turn she seemed to get progressively more attractive as her popularity increased, until she became the sultry southern belle she's known for being today (right around the time Jim Lee took over art chores, not-so-coincidentally). This one also has in-story explanation, since after the X-Men's rough battle with Nimrod that led to Nightcrawler and Rachel Summers going MIA, Rogue spent all night looking for them, but noticed that she looked like hell when passing a reflective window. Once the stores opened in the morning, she went to the mall for a makeover and liked how she looked. While her new clothes sadly didn't last, she most likely got in the habit of caring more about her appearance since then.
When Gambit was first introduced, his appearance was rather sleazy and not all that attractive. Once Marvel decided that they'd keep him on as a good guy instead of having him turn out to be a villain, however, his appearance began to improve pretty quickly.
When Wolverine was first introduced to the X-Men, he was about 5'4", quite unattractive, and apparently didn't like to bathe. Ashispopularitygrew, he became less unattractive. Then the very tall and very good looking Hugh Jackman portrayed Wolverine in the X-Men movies and people seemed to forget that one of Wolverine's old nicknames was "dog face".
Dead Girl from X-Force looked quite wizened and mummified when first introduced (see the current image for Revenant Zombie) but rapidly turned normal and hot except for her grey skin and deep-set eyes.
Even more than the above, the classic Marvel example is the Thing. His irregular, monstrous appearance in FF #1 gradually normalized; by the second year, Ben looked like he does now. John Byrne felt that this took away from the tragedy of the character, and he had Ben regress to his original look, apparently intending it to be permanent. (Byrne's views were backed up by a fan letter complaining that the Thing was ugly now, when he used to be so handsome.) Byrne ultimately restored the Thing to his iconic appearance, but would not by a long shot be the last writer to "uglify" Ben.
The same could be said for Ben's human form. In FF #1 Ben as a normal man who looked ugly since he was a more antagonistic character toward the other three members of the FF. Later in stories where The Thing (now a more lovable character) temporarily reverts back to his old self, Ben Grimm looks ruggedly handsome.
The classic comic book example is, of course, Spider-Man. Drawn by Steve Ditko, Peter Parker was a skinny, thin-faced geek and Spider-Man was thin and more spider-esque. When John Romita, Sr, a former romance comic artist, took over the pencilling duties, Peter Parker became significantly more handsome and Spider-Man took on a more muscle-bound appearance. May be Handwaved in that when Ditko was drawing it, Spidey was a teenager, and as he got older and got real exercise to go with his superstrength, his frame may well have filled out naturally.
The artists' notes in the first volume of Ultimate Spider-Man bear this out: in that series he's a high-schooler again, and he's drawn explicitly scrawnier and ganglier than the main universe version, with a note that he is supposed to be very thin, not having built up muscle from years of webslinging.
Peter does look less spindly and more conventionally attractive even towards the end of Ditko's run.
This is acknowledged in "Along Came a Child" from Marvel Comics Presents #120, which features a teenager who turns out to be the boy who witnessed Peter climbing up a building in Amazing Fantasy #15. Having figured out that Spider-Man is the same boy he saw years ago, he strikes a deal with J. Jonah Jameson, and the Daily Bugle publishes a police-sketch that accurately depicts Peter as he appeared in AF #15. Of course, Peter no longer looks like that.
Also, surprisingly enough, Gwen Stacy. In her early appearances, as drawn by Steve Ditko, she had highly, angular eyebrows, pinned up hair, a constant haughty expression, and fairly modest clothing; her features were sharp and angular and although she could occasionally pull off a nice pout, the fact that lots of characters called her pretty was the only hint to the fact that she actually was so. But when John Romita took over the drawing, Gwen was softened, her features became more angelic, she let her hair down, gaining her iconic bangs and headband, and she dressed in much sexier clothes.
It even happened to Aunt May for a few issues when Romita took over! Luckily, the fans complained she looked too young and she was soon back to her old appearance.
Songbird from the Thunderbolts is both this trope and its inverse. When she was first the villain Screaming Mimi, she was drawn anywhere from being a KISS reject to a new wave albino. Once she ditched the heavy makeup and dyed her hair mostly red, her natural good looks started shining through. This hit its peak with the Warren Ellis run, where the art direction simultaneously softened her features and refined her chin and cheekbones. The artist also gave her bright blue eyes. However after she was made a warden at the Raft, she got a butch hair cut and a somewhat more square jawline.
In a similar vein to the Thing, Deadpool's appearance was horrific when we first saw it, due to the artificial origin of his healing factor reacting with incurable cancer. Over time, it changed and simplified from "bubbles and nodules of flesh with random hair" to "flesh-coloured de-uglified Ben Grimm", and some artists go even further. In Cable & Deadpool, about 75% of his skin actually looked perfectly normal, with the rest just resembling bad acne. Didn't stop people from nearly retching when they saw him on the street. This is another that goes back and forth depending on who's drawing him, since sometimes he looks alright, others he's back to his horrific look. Since his power has been described as leaving his body tissue in constant, dynamic flux, this makes sense.
Doris Husselmeyer of Ernie started out so ugly she gave people heart attacks and went from good-looking enough that dating Arnold Arnoldski was a step down for her to getting hit on by handsome bodybuilders on the beach. Possibly because of Executive Meddling.
In issue #1 of Strangers in Paradise, Katchoo is very flat-chested and Francine's slightly overweight. By the time we come to the final issue, both women are bustier, much thinner and even have longer legs. This is evidenced by comparing the first and lastcovers◊.
Katchoo's hair also goes from really curly to practically straight by the time the series ends.
In her first appearance, Tabitha Smith (a.k.a. Boom-Boom, a.k.a. Meltdown) of Marvel's X-Titles was deliberately drawn to have a very plain face, and this was a plot point. This◊ is modern Tabitha.
Jarael from the Star Wars comic Knights of the Old Republic is supposedly designed to defy the typical comic sexbomb and be someone who "works for a living". With some slight variation Depending on the Artist, she is portrayed as a svelte bombshell, clad in a chest-emphasizing sleeveless T-shirt with flowing white hair, a supermodel face (apparently occasionally modeled on Liv Tyler) unmarred by all but the most minor smudges (she works in a junkyard) and a few cosmetic tattoos.
Jonah Hex in his first few Weird Western stories was a crouching, bulky gnomeish growler whose face wounds had tatters in places. A year later he's upright, statuesque and while the face is still disfigured the wounds are smaller and his filmy eye has gotten clearer. From Two-Face in a cowboy hat to Hollywood perfection with the mouth string thing.
Fables - Inverted with Bigby Wolf who started off looking gritty but attractive but has slowly lost most of the features of a human face. Most noticeably he no longer seems to have eyes or a mouth. Beast swings wildly in appearance from handsome to bestial depending on how much Beauty still loves him, which usually isn't much.
Sinestro, from DC Comics Green Lantern mythos, used to be drawn as a skinny guy with a huge head. As he's become more prominent, he's bulkier now, and his head is average sized. Ironically, it means he's actually looking less villainous the longer he's a villain.
In the original New Mutants run Wolfsbane had short, fuzzy, unflattering red hair (implied to be unable to grow very long at all...when she's in her human form) and a flat chest and at times would express her unhappiness at not being as beautiful as her teammate Dani Moonstar. She was (early on) depicted with a snub, almost doglike nose, sharp fangs, narrow eyes; an animalistic cast to her shape that was lost even by the end of the first issue of the regular comic. Nowadays she varies in height, often has long flowing hair and, depending on the artist, is much bustier, though her run in X-Factor has put her back to her original appearance. Her teammate Karma, a Vietnamese girl, was also depicted in an unflattering way compared to her more modern depictions, with a pug nose, downturned mouth and unflattering hairstyle. At least part of why Rahne looked as she did was her own powers interacting with with her severe problems concerning body image (she wants to be pretty, doesn't think she can be, thinks she shouldn't care because vanity's a sin and thus feel guilty for it, then feels guilty for that... thanks a lot, Rev. Craig.)
Mind you, her appearance in X-Factor deviates from the standard attractive female look but is in no way ugly, she has some Annie Lennox kinda androgynous charm to it.
When originally created, artist Bob McLeod intended Rahne to be fuller figured at 14 (issue 2), and Dani to be flat at 15. They are, too; for the first run. Rahne mostly envies Dani her long hair. '-it only grows when it's cut, and only t'this length...'
Archie Comics enters into this with the former chubby, matronly moms of Archie & Betty suddenly getting a lot thinner, and previously hideous characters like Jughead's mom & Big Ethel getting much more normalized.
In Archie's earliest appearances he was also pretty ugly, he was a scrawny, bucktoothed geek with bad acne, he later became the more handsome athletic character we know today.
Cleo, of Wet Moon, following an AnimesqueArt Shift has become somewhat slimmer & her facial features more anime. Considering creator Ross Campbell's love of chubby chicks, this was probably done for strictly pragmatic reasons.
Jenny Sparks, of Stormwatch and The Authority, was introduced as flat-chested (which had no effect on her active sex life). Whether a given artist will retain this characteristic is a crap shoot.
Iron Man - Happy Hogan was kind of like Mickey Rourke in reverse. He started out as an ugly-as-sin boxer (his Ironic Nickname stemming from the fact that he always seemed to be frowning), but as The Sixties went on, he was drawn to appear more attractive so that he actually had a prayer with Pepper Potts. Pepper herself was originally a pug-nosed, freckle-faced Girl Next Door to play up her envy of the beauty queens Tony Stark dated instead of her; she swiftly got a makeover meant to show that she was Beautiful All Along, but it somehow changed her facial features drastically.
Sensor of the postboot Legion of Super-Heroes was a giant alien snake with the ability to create illusions, allowing her to appear as a beautiful woman. But that wasn't enough, apparently, as she was later "hyper-evolved" into a more human appearance. Incidentally, since she was originally a fairly attractive (apparently) snake alien, she considered her semi-humanoid form hideous.
Black Adam started out as a villain with a hooked nose, pointed chin and slightly Sinestro-esque facial features. As his character has matured into an anti-heroic/anti-villainous knight templar type, he retained a hooked nose and arched eyebrows, although they became less prominent, but his jaw got stronger and larger, and his features more handsome, and while his features still look appropriately cruel and proud, he is now generally accepted as being good looking, to the point of The Rock being cast to play him in the film adaptation. Incidentally, the change in features made Adam look a lot like Marvel's Namor the Sub-Mariner. Their personalities are very similar to boot; it's a wonder Marvel didn't react to the new and improved Black Adam with a lawsuit.
The Sandman - Dream started out as looking kind of old and craggy when drawn by Sam Keith (he has been around since the first sentient life in the universe, you know), but most subsequent artists have him looking more or less like Robert Smith at the height of his career. Then again, since an Endless' appearance is affected by those perceiving them, this does make a degree of sense; his siblings similarly go up and down the scale of attractiveness throughout the series. Even Despair, who's supposed to be hideous, has a few appearances in the collage art for her entry in Endless Nights that look pretty nice if you're the sort who likes women with some meat on their bones.
Duela Dent, aka "Joker's Daughter" (among her other aliases) stated out with a huge pointed chin and exaggerated, clown-like features when in costume, along with having a wild purple bouffant wig. When she was brought back by Devin Grayson and Phil Jimenez in JLA/Titans, she only wore white face paint and looked much less exaggerated. Before her death in Countdown, she was also depicted as being attractive in costume, along with her hair now being red.
When depicted out of costume initially, she just looked like an average teenage girl with short hair. However, this trope got inverted for a while when George Perez drew her as a plain, heavyset woman in her New Teen Titans cameo, with bad makeup and gaudy violet hair. A Team Titans cameo then showed her as a gaunt and haggard-looking mental patient, before Jimenez and other later artists would draw her to be an attractive young woman with a bob cut.
Inverted with Raven in the New Teen Titans run, where she started out looking like a typical superheroine, and gradually her face got paler and sharper to the point where she didn't even look human, much less attractive (from the neck-up, anyway). To hear Marv Wolfman and George Perez tell it, this was purely due to Perez's evolving skill and subconscious awareness of her true nature, and they almost didn't notice themselves until they were ready to bring in Trigon, whereupon it became a plot point. Played straight after Perez left the title and Eduardo Barretto took over drawing Raven, although later artists would bring back her narrow features. After she was resurrected in the 00s era, Raven reverted to being more conventionally attractive and rounder-faced, and one moment even involved her getting a raven-shaped tramp stamp (which disappeared with later artists' depictions). To some of her fans' chagrin, she was also depicted with larger breasts in an attempt to make her look sexier, while George Perez had made it a point that Raven was supposed to be smaller-chested as part of her dancer build.
In another Teen Titans example, the first Terra was depicted as having exaggerated buck teeth, being more on the petite side, and having short feathered hair. Later flashbacks and her Blackest Night appearance tweaked her to have long hair, a taller and more shapely body, and no buck teeth to be seen.
The female Dove in Hawk & Dove has been made of this since her introduction. In her opening miniseries, Rob Liefeld infamously couldn't decide on her cup size, or even whether her costume had Absolute Cleavage, but by the time of her ongoing she subverted Most Common Superpower by having merely human-sized (large b-cup, with natural tear-drop shape!) breasts, something she was self-conscious about. Virtually every artist since has drawn her with larger breasts, however. Her human form's hair color has changed in Birds of Prey to match her costumed look, though this is more forgivable given that her team has two leggy blondes already.
As pointed out in thisStupid Comics entry, the title characters of British Girls' Comic The Four Marys got prettier and more similar-looking as time went by.
Wonder Woman's friend Etta Candy started out as visibly overweight, incredibly short (though her early appearances had her taller), and was drawn in a cartoonishly stylized manner. After she was re-introduced in the '70s, she was drawn to be of average height and she ranged from still being kind of chubby to more Hollywood Pudgy. George Perez's take on Etta started out as overweight and plain (which made her jealous of Diana), though she gradually lost weight over his run and in Bill Messner-Loeb's stories, which led to a storyline about her being anorexic. She then regained weight and was depicted as either somewhat thicker than Diana, or as heavyset as she was before. After she was brought into Gail Simone's run, Etta was revamped as a curvy blonde woman who sometimes appeared to be on the BBW side (her more athletic look was eventually implied to be from the training she got as a secret agent). Now in the New 52 continuity, Etta has been reimagined as an attractive black woman who doesn't appear very chubby at all.
Having now been granted an older body through Wiccan's magic, I now have the appearance of a young adult in their late teens/early twenties. The reaction from the denizens of the internet seems to be, and I quote, "Oh no he's hot."◊
Films — Live-Action
The Phantom of the Opera has gone from skull-faced Lon Chaney to badly-scarred Claude Rains (from the 1943 film) to slightly sunburnt Gerard Butler. If you watch clips from the original film on YouTube, at least one comment will say that Chaney is too ugly. In the original book, 'the Phantom' also works as a description of how his face actually looks: yellow skin, a few wisps of hair on his head, and no nose. The book made it quite obvious that the phantom had leprosy... yet later versions of the play, movie, and books portray him with elephantiasis... and not even the kind that you'd want to run away from.
This article shows the evolution of film portrayals of the Phantom over the years. From a purely technical standpoint, it makes a certain amount of sense, as that kind of makeup must be one hell of a pain in the ass. Still, it lacks a certain something in the "faithful to the original" department.
The original Phantom looked almost undead right from early childhood, so leprosy is an unlikely candidate for his appearance. It's unlikely that it fully reflects any real deformity or disease.
Let's not forget Julian Sands from the 1998 film. Just Julian Sands, no mask, no makeup, no disfiguration of any kind.
Emma Watson as Hermione Granger in Harry Potter. The first film practically nailed the look of Hermione right down to the mousy bed of hair. But over the progression of movies, they have more or less let the character look more attractive over time, to the point where the Beautiful All Along moment of the Yule Ball in "Goblet of Fire" is ruined thanks to the increasing attention to her looks, as opposed to the shocking reveal of the book's moment. This is because they were cast as children, and the actor's appearances changed dramatically throughout the course of the series - a great example is how Matthew Lewis looked in the first film◊ and how he looked in the final movies.◊
The young cast were also growing up faster in real life than their characters were onscreen, so when they overtook them and Dawson Casting set in, they did start to look like young adults when they should still have been gawky teenagers.
Word ofGod stated that all three of them are too attractive for their roles.
Velma from Scooby-Doo used to be kind of a dumpy girl. After the live action movie, which had an attractive woman playing her, even the cartoon versions stated being drawn more appealingly.
The first Halloweentown movie makes Luke, a goblin, look very strange in his true form (he spends most of the movie looking like a human). In the sequel he still looks weird, but it's noticeably downplayed. And then he suffered from Chuck Cunningham Syndrome and replaced by a handsomer Love Interest in the third and fourth films.
In the first two Scary Movie films Cindy Campbell is very much Hollywood Homely despite being played by the pretty Anna Faris and the second movie in particular has near constant jokes about her plainness. The third and fourth movies had Faris ditch her brunette style (copying Neve Campbell) for a decidedly more glamorous blonde look (Faris' natural hair color... also adequate to imitate Naomi Watts) and the appearance gags were dropped.
Martha Cox, one of the side characters in the High School Musical series. In the first she's a one-off gag character, a stereotypical fat nerd girl who reveals she's also a talented rapper. Her role is expanded in the second film, and by the third she's slimmed down to Hollywood Pudgy at best, her clothes have gone from dowdy to a Cyndi Lauper-esque "quirky '80s girl" look, and she seems to have gotten a lot more popular, too, becoming a cheerleader and head of the prom committee.
This has actually happened in reverse in the film adaptations of Doctor Jekyll and Mr. Hyde. In the original book, Hyde was described as looking mostly normal, but having something off about him. In most film adaptations, Hyde is portrayed as a humanoid abomination, similar to the Hulk.
Inverted, however, with Watson, who was something of a ladies man in the books, and was rather intelligent in his own right, but turned into Holmes' dumpy idiot sidekick in many adaptations thanks to the popularity of the Basil Rathbone films. In the 1980s, the Soviet adaptation and later the Granada version of Sherlock Holmes restored Watson to his original characterization, and most live-action adaptations (film and series) have followed this example.
Yarna d'al Gargan, the "fat, six-breasted exotic dancer" seen briefly in Return of the Jedi, was apparently intended to be a glaringly ugly woman. Much of the fan fiction written about the inhabitants of Jabba's palace since then has turned this characterization completely on its head. While some writers still portray Yarna as a hideous Abhorrent Admirer, most other writers have treated her much more sympathetically. Illustrations of Yarna now depict her as unquestionably female (if still fat) and try to avoid making fun of her. In a story by science-fiction author A. C. Crispin called "Skin Deep," Yarna's backstory is provided: she is an Askajian, or a member of an alien species from the desert world of Askaj. Askajians are said to only appear fat because their bodies have evolved to retain large quantities of water on arid planets; this explains why Yarna is fat on Tatooine. However, on moister or cooler worlds, members of this species are much more slender. Yarna's companion in this story, Sergeant Doallyn, even feels himself attracted (yes, sexually) to her - although he is an alien himself. Yarna also talks about how much it always hurt her to hear Jabba's henchmen refer to her as fat and ugly, even if Jabba himself was attracted to her. And in another Star Wars sourcebook, it is revealed that "Yarna" means "beautiful" in Askajian.
Mary Lynn Rajskub, who portrays Chloe O'Brian on 24, gradually received more makeup, better hair, and a more attractive wardrobe as her character grew in popularity among the fan base.
Already played by Hollywood HomelyAlyson Hannigan, Willow became steadily more attractive as Buffy the Vampire Slayer proceeded, partly from her character coming out of her shell and trying things other than the plaid skirt and pink sweater, and partly (probably) from Executive Meddling. While Willow certainly became more a colourful dresser her later clothes were not always particularly, well, fashionable ("How come you didn't tell me I look like a crazy birthday cake in this shirt?") which arguably is in character.
Occasionally her later-season outfits bordered on haute couture. Dolly Parton famously said, "It takes a lot of money to look this cheap," and in Willow's case it sometimes took trendy fashion to look that eccentric.
Roseanne. In the show, Roseanne and Dan were hard working, blue-collar Midwesterners, and Roseanne was appropriately unconcerned with her appearance◊. By the later seasons, Roseanne the actress had several plastic surgeries, lost some weight, and began wearing more flattering hair and makeup, turning her into this◊. (And this was before the final season, where everything went off the rails anyway.)
In the 8th season, the opening credits featured morphs of the main characters as they appeared in different seasons (Roseanne's can be seen starting about 0:34). The general trend is upward, though the next to last one is a definite and dramatic step downward (though that's probably at least partly due to her expression, being the only one where she wasn't smiling and instead had a sour look on her face.)
Sam Puckett on iCarly spent about three seasons as a dedicated unchanging tomboy, to the point that she is an example for Suppressed Mammaries. Once Season 4 started, the actress had grown up and out, they started showing her off in more revealing clothing. In Season 5 the only aspects of her tomboyishness are behavioural, as she has started wearing girly, fashionable and figure hugging clothing.
Elliot from Scrubs was transformed from a cute nerd to a very attractive woman, again, by Executive Meddling. It's partially justified as Elliot becoming more confident and comfortable with herself.
Also justifiable in that as Elliot's salary increased, she would be able to afford better hairstylists, clothes, and makeup. Not to mention that, as she moved up the latter from intern to resident to chief resident to private practitioner, it would be increasingly important for her to maintain a professional (which, for women, usually also means attractively feminine) look.
It's also lampshaded in-universe that she started spending a lot of time on her appearance every morning, in order to maintain her new look after her big make-over at the beginning of season 3.
Several characters in The Office (US) went through this, especially Pam. In the DVD commentary her actress, Jenna Fischer, mentions that she does her own hair and make-up for the character, at least in the earlier seasons. She has a rule that she won't spend more than a half-hour getting ready, since that's the most that Pam would. However, this all may have changed with "Fancy New Beesly" after she breaks up her engagement and begins pursuing Jim in season 3. And starts wearing her hair down... The general softening of the cast's appearances goes hand in hand with the show moving away from the oppressive pessimism of Season One towards a goofier, warmer sense of humor. Watch the last episode of Season One and then the first episode of Season Two, it's downright shocking, though the show is about as close to real life as it gets on American television as far as believable looking characters get. It wasn't until Erin came along that the show really pushed beyond what you'll see in a typical office.
Charlie Brooker makes frequent jokes about how ugly and style-illiterate he is, admitting in a column that his haircuts are left up to the whims of his barber. As his TV career took off, however, he's frequently seen wearing nice clothes and sporting a longer, much more flattering hairstyle, his skin has become gradually nicer since he quit smoking, and he's lost weight. It's nice to see and it doesn't make him any less funny, but his stage persona's jokes about his ugliness, such as describing himself as "the result of a drunken bet at the face factory", don't make so much sense now that he's conventionally attractive.
Rose from Two and a Half Men was first depicted as ugly woman, but the actress was too good looking, so her character was developed into a creepy stalker.
Both Connor and Abby from Primeval were fairly unique looking when the series started out. Connor was a greasy haired nerd who dressed in a strange mish-mash of clothes and wonky hats while Abby was a bit of a punk chick who wore too much makeup. By the fourth season they had started dressing in more normal clothes and had much more flattering hairstyles. But they both kept some of their characters' original styles, just without going overboard.
The Halliwell sisters in Charmed started the first season out with fairly ordinary and normal clothes and rather plain hairstyles. By season 3 they were wearing the latest fashions and their sex appeal was played up. Then around season 5 the outfits got really vampy.
Demons as a whole got progressively prettier too, or at least progressively more human-looking. Some of the early demons were hideous or scary, while many of the later demons just looked like dark-haired people in leather. There was a justification for Cole, as he was going through the Heel-Face Revolving Door and how demonic he looked depended on what side he was on, but sometimes demons just looked human with little reason.
There was actually something of a reason, albeit one that was never addressed directly. It was said that in the universe of the show, the stronger, more upper-level demons are usually more human-looking (since interacting with humans makes it easier to gain power, and more power makes it easier to "glamour" and pass as human.) As the Charmed Ones got progressively stronger and their reputation began to build, the stronger (and therefore, more human-appearing) demons began to be the ones who came after them.
Topanga on Boy Meets World was originally wore frumpy clothes and had wild, unruly hair to demonstrate her Granola Girl personality. However, as her personality shifted to being a normal Girl Next Door and the actress grew up, she was given more attractive clothes, hairstyle and makeup.
Debra Barone on Everybody Loves Raymond where the first season Patricia Heaton had a short, unflattering haircut and dowdy stay-at-home mom clothes. As the seasons went on her hair was longer and better styled and her makeup and outfits more flattering.
This was always the plan with Guinevere from Merlin. The costume designers and makeup artists dressed down Angel Coulby to the point where some unpleasant fans complained that she wasn't pretty enough to play the part at all, only for her appearance to get more care and attention as the show went on. Fast-forward to series five and the first on-set photographs of Queen Guinevere are posted on the internet - the fanbase responds by going nuts over how beautiful she looks.
Inverted by Mac in It's Always Sunny in Philadelphia, when Rob McElhenney put on 50 pounds for season 7, in a deliberate effort by the actor/creator to defy this trope.
Travis, The Dragon in Blake's 7. When he was played by Stephen Greif in the first season, his missing left eye was covered by a huge, ugly, blackened-metal prosthesis that appeared not just to be covering his eye socket but actually replacing a large chunk of his skull. When, in the second series, the character was recast with Brian Croucher (who wasn't any better or worse-looking than Greif otherwise), he was given a much smaller and more ordinary-looking eye patch.
Possibly justified by a few lines in his first appearance, where Servalan comments on the fact that the original prosthesis was a very crude and hasty field-expedient and he could have most of the cosmetic damage undone, but apparently Travis keeps it to prove he's a proper soldier who's seen real action. It'd be quite easy to Hand Wave the changes as further surgery being needed because it wasn't healing properly or something, but the writers never got around to addressing it. The out-of-universe explanation is probably a purely practical one; the original prop would have been a royal pain to make, apply and keep in place.
In Kamen Rider Fourze, Tomoko Nozama goes from being an awkward-looking Goth teen to having more subtle, flattering makeup and accessories and a longer hairstyle (especially around the time that the actress was preparing to release a photobook.) Continues in a post-series movie where after a Time Skip she's grown into a very beautiful adult.
In Doctor Who, the Fourth Doctor started out wearing a shabby mishmash of clothes that didn't match at all based on an "eternal art student" concept. He transitioned to dressing in a much more expensive-looking Victorian-influenced style based on a Byronic Hero/"cheerful gothic horror" concept, though the scruffiness remained as a significant part of his character (so his clothes were usually crushed, faded, missing buttons, done up wrong, etcetera). In his final season, however, a new producer ordered the costume designer to toss out the 'shabby' look in favour of something that was "new and shocking", had a "polished" look and could be sold as Official Cosplay Gear. His last outfit is based on 1920s Russian military gear and has virtually no scruffy elements besides his Messy Hair.
Mythology and Folklore
Succubi were originally supposed to be ugly, but have evolved to be seductively beautiful. This also tends to correspond to how the legends have evolved - initially, they were creatures who just raped men in their sleep (thus being the source of erotic dreams and nightime ejaculations). Over time, the legend changed to succubi having to actively lure their victims into intercourse - thus, depictions shifted to depict more and more attractive creatures as logically, an ugly creature would have trouble getting a willing victim.
In Greek Mythology Medusa is turned into a hideous monster with a head full of snakes. That is, her face was so hideously ugly that she could turn people to stone by looking at them. Originally, she also had wings, scales, huge claws, and massive fangs. These days, film-makers and fantasy artists have ditched the ugliness in favor of the snake-hair and made her petrification powers the result of inherent magical powers that are based in her eyes. As such, we have the likes of Uma Thurman in Percy Jackson and the Olympians as a gorgeous snake-haired woman, a Cute Monster Girl in Clash of the Titans, and an attractive actress in the Hallmark TV movie The Voyage of the Unicorn who is simply given sunglasses in order to make her safe enough to interact with other characters. At least one source covering the original myths (Bullfinch's?) had her sisters being hideous, but she herself maintaining her mortal beauty, presumably because Athena (jerk that she is) wanted it to be more ironic. Some myths offer a compromise and state that Medusa was both beautiful and terrible at the same time. The Clash of the Titans remake follows this and has Medusa appear beautiful but then change when she attacks.
Sirens were supposed to be bird women, but in modern times we tend to think of them as beautiful mermaids. To the point that in some languages the word for "siren" and "mermaid" is the same, so the two are basically equated, and "sirenian" is the scientific term for manatees and dugongs.. Some modern depictions of sirens still use the bird-woman rendition. Martin Mystery had an interesting interpretation of this concept. The siren could be a beautiful, blue-haired woman one moment, a vicious (but still pretty cool) bird monster the next. Even before they became mermaids, sirens were first depicted as birds with women's heads but then became beautiful women whose bodies as well as their voices were seductive.
Mermaids themselves have experienced this. Early British reports of them described them as monstrous with tails 2000 feet in length more akin to sea serpents. They quickly evolved into the beautiful and normal sized creatures we're more familiar with. They've also experienced inversions with many works twisting them into horrific monsters.
Valkyries from Norse Mythology were originally demons but eventually became beautiful shield maidens.
Joanie Laurer, better known to Professional Wrestling fans as Chyna, started her WWE career as a mannish-looking, Amazonian bodybuilding thug. Then she got implants, had her jawline shaved down, and some other cosmetic surgery. Then she kept getting cosmetic surgery, which turned her into what wrestling fans mostly called a "plastic train wreck". She also lost most of her muscles, which gave her body some weird proportions as the surgery had been done for her muscular physique.
In general, WWE Divas who are brought in from the independent wrestling scene go through so many cosmetic surgeries while in the developmental leagues that by the time they actually debut in WWE, they look nothing like they used to. This is especially galling considering that some of the girls who get expensive surgery done while in developmental frequently don't get called up to WWE. Angel Williams (best known for her run as Angelina Love in TNA), for example, was beloved by the fitness community for her natural abs before getting called into WWE developmental and told to soften up and get implants. Then they dropped her.
Inverted with Molly Holly. When she was brought into WWE she was a pretty sweet country bumpkin with blonde pigtails. Then she was repackaged as a self-righteous prude where she dyed her hair brown, cut it short and started dressing in dowdy and conservative clothes. This got reversed in 2003 when she started wrestling in corsets and her hair grew out.
Eberron'sShifters originally looked like this◊ - and this is a female. However, later artists drew them either as being basically Hugh Jackman as the Wolf Man if male, and more like a wilder elf if female, seen here◊; or emphasizing the more Cat Girl-like qualities of females, as seen here◊. This, of course, made Shifters far more popular than the Gonk-ier initial portrayal did.
Zigzagged with the Daemonettes of Slaanesh in Warhammer and Warhammer 40,000 who in their first appearance looked ridicolously hideous. Then came the second variant which was the prettiest model range in the entire game. Then came 4th edition and Daemonettes went right back to hideous (though not ridiculous).
The eponymous character from the Max Payne series. Max was modelled on Sam Lake, one of the game's writers, for the first game, and ended up with a near-perpetual squint and constipated face. For the second game, actor Timothy Gibbs was hired as the base, so Max looked noticeably more generic. In the third game however, Max shaves his head and grows a rather thick beard.
Kana from the Visual NovelKana: Little Sister was drawn very realistically for someone dying of a renal disease, her body oddly developed due to poor bone growth. As such, the endings where she dies and the main character sees a vision of a healthy and well-proportioned Kana are even more emotional than they would be otherwise. Unfortunately, the people who made the remake seemed scared that people would find her "ugly", and remodelled her to a generic implausibly attractive Ill Girl. Some of the major differences are pointed out here.
Of course, the original Kana still has features that are considered attractive, at least in Japan, since she is light-skinned and very petite, making her kawaii. The player character often comments on this.
Calypso, Big Bad of Twisted Metal, lost his wife and daughter in a car crash that left him horribly burned. In the original game, Calypso had a face like raw hamburger... but as it was a real person in makeup, the result was kind of embarrassing. The second game handled this much better with its animated endings, creating the definitive Calypso - still obviously scarred, but not as ridiculous. In the third game, the scars were reduced, and gone by the fourth. This could be written off as 989 having no clue what they were doing. In the Incog Inc. games (made up of several former Singletrac employees), Calypso doesn't look anything like he used to for some reason... but he still has no scars, aside from his missing eye (which he loses without explanation between the second game and Head-On).
Reno in Final Fantasy VII at first wasn't supposed to be a pretty boy, (in contrast with Rufus for instance ◊). Later the Compilation gave him Generic Cuteness to bring him in line with fandom portrayal of the character.
The film Advent Children made Barrett more conventionally attractive... and gave him a fishnet vest...
Otacon from Metal Gear Solid is an arguable case, as he progressively looked less scruffy, gained better-looking glasses, and his hair became less of a mess. His hair also goes from grey to dark brown, his eyes go from brown to blue (making him resemble blue-eyed-brown-haired Snake), and his build goes from skinny, to slim, to broad-shouldered and fit. Not to mention his fashion sense improves, from the incredibly ugly and oversized duffle coat he wears in the first, to a stylish, slimly-cut white coat partnered with black gloves in the fourth.
Some of the characters in the Pokémon Gold and Silver remakes are more attractive now than they were in the original. Morty is a prime example. Originally only somewhat attractive, in the remakes he's a full-on Bishonen. Will, Ariana, and Archer are also more attractive in the remakes than in the original. Even Pryce is upgraded from a somewhat ugly old man to looking very good for his age.
In the Splinter Cell: Conviction forums, a number of fans have expressed distaste at the UbiSoft's drastic change of Anna Grimsdottir. In the first two games, she wears glasses and has a haircut and outfit befitting an office worker or bureaucrat. She lost the glasses (sorry meganekko lovers) and looked a little prettier in Chaos Theory but still bore a resemblance to her past versions. In Conviction however, she looks much more conventionally attractive than in the other games.
Dynasty Warriors is very guilty of this for most of its roster, with Zhao Yun being a prime example. The third◊ fourth◊, and fifth◊ games aren't too bad, but then once you reach the reboot in the sixth◊ game he's getting too pretty for his own good, but in the seventh◊ game he's a frickin' Jpop star!
The majority of the characters in the Star Fox series became prettier looking, especially Wolf, Fox, and Leon where their faces and eyes look more pronounced and defined compared their more basic and gruffer looks in the past.
The hyenas in Digger gradually become less monstrous-looking (and more anthropomorphic) as they become more sympathetic (read: aren't hunting Digger).
Bootsie from Friendly Hostility started out skinny and awkward, but eventually ended up being acknowledged in-series as attractive. This might have something to do with her leaving behind her years as an unpopular teenager and growing into a more confident adult who's actually comfortable in her own skin.
Not a straight example, but Reynardine/Renard from Gunnerkrigg Court seems to spend less time as his small, angry teddy bear form and more as his impressive, proud-looking wolf form as his backstory is explored more and he becomes less of a comedic snarker and more of a sympathetic (and mystic) character.
In the first season of Avatar: The Last Airbender , Zuko was not exactly conventionally attractive (although he did get his fair share of the fangirls), what with his death-white skin, constant scowl, bright red scar covering a quarter of his face and a quite frankly bizarre hairstyle choice, but as the show went on and he very slowly Heel-Face Turn-ed, his hair grew out and his skin tanned slightly, which had the added benefit of making his scar less noticeable, he went from scowling to moping and then smiling, and he even seemed to bulk up a little. His Good Costume Switch helped as well.
From the sequel series, we have Tenzin's son Meelo. He was kind of ugly in season one with a big head, googly eyes, and several missing teeth. In season two he is much cuter as his head is more proportionate to his body, his eyes are more focused, and he has most of his teeth. The teeth at least can be justified as him having grown in new ones since he's a child.
Both Hank and Peggy from King of the Hill benefited from this. Peggy received some color in her skin, lipstick and more normal looking eyes. Hank, though never what you'd call handsome, had the excess lines vanish from his face so he looked like a guy in his forties and not a constantly angry old man.