Power corrupts, and it seems like it corrupts the meek and good-natured quicker than everyone, given half a chance. Before too long, that nice person with a cheerful greeting and understanding ear for all will turn into a dictator, their ego completely out of control as a result of their new responsibilities and being given their chance to make a mark and implement all their good ideas. In the name of 'efficiency', they'll create countless petty and pedantic rules for all to follow — all of which will be staggeringly inefficient, considering the place ran smoothly before without them and that their implementation only slows things down. And don't even think of trying to circumvent them — the new boss have developed a sadistic streak which will lead them into enthusiastically punishing even the slightest infraction of those rules in a fashion that is completely out of proportion to the offense. Some sort of ranking or points allocation system which is just designed to irritate their co-workers and stimulate inferiority complexes will probably be implemented. They'll also plunge deep into full-blown paranoia, convinced that everyone is plotting against them. Even the character's fashion sense will most likely be altered to emphasize their new workplace-fascist mindset. Everyone will be shocked by the drastic change in their friend, but any attempts to talk them down will be rebuked, and the person who tried to talk them down will usually be summarily fired.
They've become Drunk With Power.
It's a Face-Heel Turn, but usually a very minor and temporary one; usually, the newly promoted tyrant's conduct will result in either everyone being fired for breathing or quitting en masse in protest, just in time for a fresh crisis that plunges the tyrant completely out of their depth, resulting in much humiliation as they either have to go crawling back to everyone they've just been bullying to meekly ask them to come back and help them fix things before the boss arrives, or for the boss to actually arrive (often unexpectedly early) only to see exactly what chaos has resulted in their absence.
Usually, after such a humbling and humiliating breakdown and the resulting reality check, the tyrant will be utterly appalled by and ashamed of their own conduct ("I don't know what came over me!" being a frequent lament), but will soon be forgiven by all and will return to their usual good-natured selves, if a little bit humbler and wiser. If the promotion wasn't temporary, they may even voluntarily relinquish it, having decided that they were becoming someone they didn't like.
Often found in the Work Com. With Great Power Comes Great Insanity and A God Am I are this to the extreme. See Drunk on the Dark Side for the superpower equivalent. When it occurs due to elevated expectations and wedding-related stress, see Bridezilla. Compare Acquired Situational Narcissism, Screw the Rules, I Have Money!. See Screw the Rules, I Make Them! for when someone tries to justify their actions even when their position does not give them authority to do so.
open/close all folders
Anime and Manga
Magical Project S: Eimi, the hall guardian of her school, is constantly enforcing the rules (even outside school or when close of dangerous situations) to the point that when she gets superpowers, she still enforces the school rules.
The character arc of Harry McDowell in Gungrave: from street kid seeking an escape from poverty to absolute bastard in charge of the Mob.
Happened in the Patlabor episode The Seven Days of Fire. The Chief Mechanic goes on vacation and leaves his Number 2 in charge; shortly after he found the mechanics' massive Porn Stash, burned it and began imposing ludicrous restrictions on them. This kicks off what amounts to a civil war, with warring factions forming and dissolving left and right (although no faction ever had numbers in the double digits) until the Chief comes back a week later and puts and end to it.
Popcorn Avatar: According to Lisa, this was Indra's fate prior to incarnating as Amano.
Raul the Cat quickly becomes this when he is elected mayor of Chicago in American Flagg. He also becomes drunk, on Gato Blotto™ provided by a real estate developer.
"It's beautiful! IT'S ALL MINE! ALL THIS STUFF IS MINE! THAT'S MINE, THIS IS MINE, IT'S ALL MINE! I HAVE COMPLETE POWER! IT'S ALL MINE!"
In the Pony POV Series' "Origins" arc, Havoc's avatar was so fueled by the chaos of the Alicorn/Draconequi War that him/it was driven insane. It got to the point that the avatar had Discordeat his own brother (something Havoc would never do, as his children's well being is something he genuinely cares about) before letting him/itself be devoured as well, all to increase Discord's power and ensure the spread of chaos.
It should be noted that later, Rancor would state that the Avatar had gone insane by Draconequusstandards.
A variant is used in Woody Allen's Bananas. After overthrowing the government, the rebel leader begins to make absurd demands, such as changing the nation's language to Swedish and having all underwear worn on the outside. One of his underlings observes, "He's gone mad with power!"
In the Walking with Dinosaurs movie, Scowler was a Jerk Jock who entertains himself by picking on Patchi. But when he becomes the leader, he kicks Patchi out of the herd and refuses to listen to anyone else due to being the leader.
In Discworld novel The Fifth Elephant, Copper Who Doesn't Do Anything Fred Colon finds himself the most senior officer in the Watch after Vimes, Carrot, and Angua all go to Überwald for the book's A-plot. The normally laid-back Sgt. Colon almost immediately snaps under the pressure and becomes the authoritarian and paranoid Captain Colon, firing and demoting people left right and centre and causing the rest of the Watch to go on strike. He's an unusually sympathetic example in some ways, however, as he knew he was out of his depth and his behaviour is as much a book-long Freak Out as it is this trope. Besides, you can't help but feel for poor Fred when it occurs to him that Commander Vimes will be coming back at some point and will not be at all amused when he sees what's been going on in his absence... Carrot gets to the Watch House first, Sam being somewhat preoccupied with Sybil's big news, and apparently manages to sort it all out.
Marla Karuw in Star Trek: The Genesis Wave, who eventually succumbs to megalomania after being appointed regent of Aluwna. She was formally in prison, but was pardoned and given power in a desperate attempt to save Aluwnan civilization during the crisis.
“Ambassador, you sent me that story... about the ancient Terran named Noah. You didn't think I would read it, but I did. You were right - it did give me inspiration, because it was about a lone person who listened to his inner voice, the Divine. That voice told him to build the ark, and he ignored everyone else on the planet, all those who thought he was a fool. Single-handedly, he brought his world through turmoil and saved all the species on the planet. One person! Yes, I could identify with Noah. Now we are finally at the end of the storm; the clouds are parting, and the flood waters are receding. I can't believe that anything will stop me from my victory”.
He is drunk with terrible power, and the blows he strikes at his enemy may well bring down the kingdom.
Live Action TV
The Dukes of Hazzard: Rosco was already one of the show's villains, due to his never-ending desire to catch the series' protagonists and his alignment with the corrupt Boss Hogg. But give him money – $10 million, to be exact – and Rosco turns from the inept, Wile E. Coyote lawman to a power-hungry, money crazed despot. (Well, not really a despot, but...) That's exactly what happens in Season 4's "The $10 Million Sheriff," where Rosco thinks that he's inherited a fortune, hires a criminal to hunt down Bo and Luke (in exchange for a $100,000 payoff)... and most tellingly insults Boss and wipes him out in a rigged poker game. The trope is quickly ended when Rosco finds out he didn't really inherit $10 million.
Londo Molari from Babylon 5 can be quite accurately described as addicted to power. In his heart, he is not an evil man and simply longs for the good old times when things were easier and safe. But being from a species that has Magnificent Bastard and Chronic Backstabbing Disorder as its hat, he is too easily drawn to take part in conspiracies to increase the prestige of his species and himself. At several times he realizes that he has fallen in with the wrong crowds and he is helping them doing far more bad than good, but he simply can't live with the thought of loosing the respect of his allies or the embarasment for his species if the conspiracies are publically exposed. When confronted he gets violently angry and denies everything. One time he manages to break free and accept the ridicule he gets for being a cowardly men who abandons his position and duties, but then his favorite concubine is murdered, which instantly has him get in contact with his most powerful connections and promises them to do anything they want and abandon all his moral objections, if they help him getting his revenge. It was actually the same people who had her murdered and anticipated that very reaction, because Londo is just so easy to manipulate if offered with power and threatened with damaging his prestige.
Hank Kingsley becomes one in The Larry Sanders Show episode "Hank's Night In The Sun," after he is given the chance to guest-host the show due to Larry suffering a bout of food poisoning. A slightly unusual example, in that no one really thinks he's up to the job and both Larry and Artie are aware that Hank is exactly the type of person who will become a raging egomaniacal "Ass of the Western World" if given such responsibility, but are forced to let him do it due to the last-minute nature of Larry's illness. True to form, after his initial appearance (in which he is bumbling but humble and self-deprecating, which the audience engages with) Hank becomes impossible to deal with - so Artie and Larry let him go on for a second evening, during which he is still incompetent and bumbling, but the audience finds his newfound arrogance so off-putting that he is booed off the stage, thus providing him with a humbling come-down.
Spoofed in NewsRadio, when Matthew is given a promotion and it immediately goes to his head. Thing is, the promotion is a purely 'in-name-only' kind of thing, with absolutely no increase in authority or influence at all, and in any case his attempts at throwing his weight around are so petty and inept that no one pays any attention to him anyway. He still gives it up at the end anyway, citing that he's becoming someone he doesn't like.
Played perfectly in an episode of Home Improvement, where Wilson becomes the director of a previously laid-back production of Romeo and Juliet at the school and the episode morphs rapidly into a Tyrant Takes the Helm story.
Happens to Jack in Power Rangers S.P.D. after jumping straight from "homeless struggling to survive" to "leader of elite police squad". He learns not to abuse his power by the end of the episode and remains leader through the end of the series.
Dwight is given the task of choosing the company's health plan, and quickly gets delusional about it. Jim notes that it's the smallest amount of power that has ever gotten to someone's head.
In the original UK version, Gareth was in a near-constant state of this as a result of his 'promotion' to 'Team Leader', which Tim perceptively notes is not a promotion at all, merely a job title someone has given him to encourage him to take on an increased workload for no extra money. Curiously enough, when he gets promoted to being the office manager when David is fired, there's no noticeable increase in his arrogance or paranoia - which, granted, is not exactly saying much, since he's a pretty unpleasant person to begin with. Furthermore, even with his real promotion, no one pays the slightest bit of attention to him anyway.
The fourth season of the US version features this a few times: Jim is put in charge of the office and attempts to turn all the birthday parties into one, which is met with disdain from the staff (who treat him as if he'd gone mad with power). Former temp Ryan is promoted to corporate and likewise goes mad with power, to the point of conspiring to have Jim fired and committing fraud when it seems as if his groundbreaking new plan to revitalize the company, won't.
In an episode of The Goodies, Graeme's plan to set up a pirate radio station (and pirate post-office) and the resulting success soon turns him into a raging fascist dictator, complete with uniform and ranting Germanic accent, and he develops a mad plan to drag the entirety of Britain outside of the five-mile limit so that he can rule over it as a 'pirate state'. When Bill and Tim walk out on him in disgust, he eventually resorts to trying to tow Britain away single-handedly in a rowboat.
In fact this sort of thing happens rather a lot in The Goodies, for instance it happened to Bill in Kung-Fu Capers episode, Graeme AGAIN in the Bunfight at the OK Tearooms and all three of them in the Movies.
In Happy Days, there were two notable examples: subverted when Richie was in the ROTC as the acting officer in command, and invoked when Sheriff Kirk tried to run The Fonz out of town, as well as forcing business owners to adhere to his rules.
In Are You Being Served?, Mr. Grainger was put in charge at one point when Mr. Rumbold was called away for a business meeting. He immediately began to throw his weight around... until it became Lonely at the Top.
Frank Burns from Mash regularly got drunk with power: if the Colonel made the mistake of leaving him in charge for more than a day, he would create ridiculous rules and go through pseudo-military drills to prepare them for "the enemy."
In one of the several instances of 'Frank in charge', there was a partial aversion when Frank decides that the medical staff is getting too alcohol-dependent, and declares the 4077 'dry'. He's a jerk about it, overbearing and shows all the signs of the trope... but it becomes clear as it goes along that Frank is more-or-less right. Hawkeye and Trapper even find themselves asking themselves in horror if Frank has a point after they almost tear into each other over something trivial from booze withdrawl.
Frank's replacement, Charles Winchester, went another way: when presented with power, he didn't lord it over the camp. He mainly used it as an excuse to drink more and get extra time off his shift, and the rest of the camp ran as efficiently as ever. However, in one episode ("Tell It to the Marines") Winchester assumes command in Potter's absence and turns Klinger into his personal valet.
Semi-averted in "Commander Pierce". While Hawkeye does start acting authoritarian and in the way he normally despises officers' behaving, it's clear that it's because he's discovering the real problems and headaches of command in the absence of Potter and incapacity of Winchester. As CO he can't afford to only look at his own problems any more, he has to consider the needs of the unit... and suddenly he finds himself doing the stuff he hated in previous commanders.
When Daniel Jackson of Stargate SG-1 gains the ancestral knowledge of the Goa'uld, he quickly promotes himself to world emperor, nukes cities and kills his friends. This is shown to be All Just a Dream. Subverted later when he actually gains the (much greater) knowledge of the ascended, and remains the compassionate hero we know him as.
Has happened a number of times on Hogan's Heroes when the prisoners have let Schultz think he's boss for various reasons and have found it difficult to 're-tame' him.
JAG: In "Tribunal", when Admiral Chegwidden is away overseas and has designated Lieutenant Singer as Acting JAG, one of the first things she decides to do is to have a fire drill and to have Lieutenant Sims to review and update all internal administrative manuals.
Parodied on a Saturday Night Live sketch concerning Al Gore paying a visit behind the scenes of The West Wing following his election defeat to George Bush. At one point, Gore good-humouredly asks he if can briefly sit behind the desk in the 'Oval Office'... and over the course of the skit becomes increasingly egomaniacal and tyrannical, and refuses to leave despite the cast's repeated insistence that it's just a mock-up of the Oval Office, and he doesn't actually have any more power at all.
Mystery Science Theater 3000 — anyone who unexpectedly was given authority almost immediately began throwing their weight around in this manner.
In his first appearance, TV's Frank vehemently declared that there's a new sheriff in town to Joel and the 'Bots... then went straight back to taking their order for take-out.
When Pearl Forrester places him in charge of the Satellite of Love as part of a variation of Philip Zimbardo's Stanford prison study, Tom Servo is gussied up as a Fascist dictator and demanding that Crow and Mike (now done up like downtrodden masses in chains) that they turn over their cookies before he has them torn in half by Sumo wrestlers, before she's even done explaining the nature of the experiment. Given that her version involves having fire ants dumped down his clothes, he should have waited another minute.
In a later episode, Crow doesn't show himself to be much better, instantly becoming an abusive babysitter when Pearl leaves him in charge.
Both Captain Mainwaring and Warden Hodges of Dad's Army represent recurring character examples of this trope; both have let the authority and power that their new wartime positions have given them go straight to their heads, and neither show any signs of coming down from the power rush they've been given.
Private Fraser represents a more standard version of this trope in the episode he's temporarily put in charge of the Home Guard unit. Curiously, he still manages to do the job more efficiently than Mainwaring usually does.
A sketch on Kids in the Hall did this when the mailroom clerk is given a promotion. Not two seconds after receiving it he instantly goes mad with power (even admitting it) and starts to boss around his co-workers.
"Okay, let's review your first week as second assistant manager. Oh, you came in on time every day. That's good, that's really good. But you killed Perkins, and that's bad."
On Remember WENN, this happens to Mackie Bloom after Betty temporarily places him in charge of the station.
Subverted with John in Farscape once he can make wormhole weapons. He even lampshades the possibility by saying "Absolute power corrupts absolutely" after the knowledge is unlocked. However, he manages to stay on track and not go power crazy during the standoff and after he wakes up from his Heroic BSOD after shutting down the weapon he's still his old self.
In Community episode Contemporary American Poultry the study group gets increasingly spoiled and obnoxious the more powerful they get. Curiously enough, however, Abed himself seems more Drunk With Actually Getting To Connect With People For Once.
Once Regina in Once Upon a Time started on getting revenge on Snow, she slowly became more and more addicted to using magic. In season 2, she decided to stop using it and is treating it like a drug addiction and seeing Archie for help to treat it.
Hale in Lost Girl starts out as nice guy, but once he becomes the Ash in Season 3 he winds up taking a level in jerkass. He hasn't particularly abused his power, but he has adopted the Fae's attitude towards humans. Lauren however, who has gotten thoroughly sick of the Fae treating her this way, dismisses this idea. She claims that power doesn't change people, it shows them for who they really are.
Harvard from Ground Floor puts himself in charge of the building support staff when Jenny temporarily becomes Mansfield's assistant. He immediately launches into a version of the famous Glengarry Glen Ross speech using Pop Tarts as an incentive. He's Hoist by His Own Petard soon enough, though, as everyone walks out as he's talking (taking the Pop Tarts with them) leaving him to deal with 'New Phone Day' on his own. He ends up accidentally locking himself in a cage.
The Doctor slips into this from time to time when he doesn't have a companion to reign him in. Most notably his A God Am I moment in The Waters of Mars. Lets just say that 1200 years of constant victories of 1 man vs. the universe has given him a bit of an ego, and he needs a human by his side to keep it in check.
Immediately after Sarge's funeral in season five of Red vs. Blue, Simmons declared himself Red Team leader and took mere minutes to become corrupt.
Grif: You have gone blind with imaginary power, Simmons!
Simmons: Oh ho ho, on the contrary. I think I've gone blind with very real power.
Alice became one of these when she temporarily replaced the Pointy-Haired Boss in a Dilbert arc, to the point she started wearing a crown and scepter.
Similarly, Wally attempted this when he got himself put in charge of moving to a different building, threatening to abuse his power to assign people cubicle locations: "I banish you to the cubicle closest to your boss!"
In Foxtrot, Peter Fox becomes a complete tyrant whenever he gets even a miniscule measure of power, treating (or at least trying to) his subordinates like servants or slaves, at the very least acting very obnoxious to them.
Grytpype: Mister Seagoon, how long have you been with us?
Seagoon: Twenty minutes.
Grytpype: What a splendid record of devotion and honesty. Neddie - and this is where the story really starts - Neddie, I am putting you in a position of trust. You're going to be in charge of the gold vault. Here is the key.
Seagoon: Gold? GOLD! Ha ha ha ha ha, the gold, ha ha ha, the lovely gold. I'll be rich, ha ha ha. All right for me, gold, ha ha ha ha, the GOOOLD!!!
Grytpype: ... I wonder if he's the right man for the job?
Wheatley from Portal 2 demonstrates this once you reach the midpoint of the game, when he takes over GLaDOS' chassis, repeatedly commenting on the newfound grandeur. Followed by a laugh. Then it goescrazy.
In the Knights of the Old Republic game, the Sith initiates on Korriban are all Jerkasses who abuse their power. One in particular, however, is hanging out at the docking bay just zapping the crap out of people because he's so elated that he can. Unless you're a complete prick, his death comes swiftly.
VlogBrother John Green got drunk with a very nerdy kind of power in one of his videos. "I will have the teaching power. I am the English teacher! I am mad with power!!! [violent camera shaking]" It was closely followed with a more toned-down comment:
People in the neighborhood look at me funny when I scream into the camera while walking.
In Kickassia, MarzGurl. She punches recruits to keep them in line, and asks Linkara if he has when he's doing their FBI surprise training.
The Nostalgia Critic darkly deconstructs this one. He's so powerless usually, all his life even, that any whiff of power makes him cling onto it so hard he'll even consider suicide to keep it.
An old Lore Brand Comics parodied the trope, picturing Lore with drinks in hand proclaiming, "I'm drunk with power!" "No wait... buttershots." "I'm drunk with buttershots!"
In an episode of The Simpsons, Bart's newfound interest in law-enforcement sees him team up with Principal Skinner to rapidly become a fascistic hall-monitor, at roughly the same time that Lisa, disillusioned after being told she'll never be a jazz musician, becomes the school rebel. In order to save Lisa from being expelled after she steals the teacher's copies of all the school textbooks, Bart reverts to his old ways.
The show also provides a subversion of this: Homer, who has been discovered to be a foretold prophet of the secret 'Stonecutters' organisation, has briefly gone through a mild A God Am I stage but gets a bit sick of the constant grovelling and decides that, instead of just throwing his weight around and wasting their time with hedonistic frivolity, he'll lead the Stonecutters into helping make the world a better place and enriching their lives. Unfortunately for him, the rest of the Stonecutters quite like the hedonistic frivolity.
A more low-key version happens when the MENSA takes over the Springfield city government; their "completely rational" rule is initially not so bad, but they start disagreeing and splitting up shortly after reaching the power. The people of Springfield are also less than impressed with some of their latter initiatives, including Comic Book Guy's proposed ordinance of citizens having sex only every seven years (which will mean more for him, in any case). They quit once Stephen Hawking makes them realize their mistakes.
In "The Old Man And The Lisa", Mr. Burns loses all his money and Lenny is the new boss of the power plant. Even though he isn't used to the job at first and we don't get to see him doing his job, Mr. Burns returns as owner of the plant and Smithers says "Lenny's reign of terror has come to an end".
Russ Cargill - head of the E.P.A in The Simpsons Movie, is a textbook, if self-aware, example of this trope, as seen in the quote up top.
Another episode subverts this. When Homer becomes head of the Indian branch of the power plant, it looks like he's set himself up as a god, but it turns out he was such a Reasonable Authority Figure they loved him as if he was a god.
Rocko in Rocko's Modern Life is left in charge of the comic book store while the boss is away. Brainwashed by the boss's massage chair, he becomes greedy and ill-tempered, and starts to look like him.
Heffer after he becomes a security guard at the Conglom-O building.
Gus became this in Recess when King Bob appointed him temporary monarch of the playground.
In a more bureaucratic fashion, it also happened to TJ; when the whole playground started using stickers as a form of currency, TJ went from rags to riches to Corrupt Corporate Executive, implementing extortionate fees for every form of entertainment on the playground.
In Storm Hawks, Finn quickly goes mad with power after being left in charge while Aerrow is away, eventually provoking his teammates to mutiny against him.
Pity the poor soul who puts Eric Cartman of South Park in a position of (as he calls it) "authorituh." The first time it happened was when he was deputized, and he quickly becomes a Rogue Cop, patrolling the streets on his Big Wheel tricycle and bludgeoning anyone who looks at him funny. In a more extreme example, when he played Stonewall Jackson in a Civil War reenactment, he nearly succeeds in reestablishing the Confederacy. And then there's the time he formed a Mel Gibson fan club and nearly started another holocaust.
In Cartman's case his actual character does not change - he's always a sociopathic brat - but sometimes he happens to get power to act his ideas in reality.
He became a hall monitor, and quickly transformed into Dog The Bounty Hunter, using Bear Mace on anyone who was even close to being in his way.
In an episode of DuckTales, Fenton Crackshell is obliged to impersonate Scrooge, who has gone missing, and soon starts acting like a caricature of Scrooge, with all his negative personality traits at full blast and none of the mitigating positive ones, even when he's alone with people who know about the impersonation.
In an episode of Wayside, Myron gets tagged it and becomes the most powerful person on the playground. The end results aren't pretty. In fact, you can't even dare tag Myron it, because everyone knows what happens.
In the Mickey Mouse Works short "Sandwich Makers", Goofy is put in charge of a sandwich shop with Mickey and Donald as workers. Goofy eventually takes his "How To Be In Charge" book seriously and grows mad with power as 'captain', calling his friends yeomen and throwing them in "the brig" (storage closet).
Goofy: "Chapter Three: Who Needs Friends When You've Got Power!" (thunder crashes)
When Sponge Bob Square Pants is made hall monitor, he tries to direct traffic, set an example of why not to leave windows open, and heads up a two-man manhunt for himself.
Numbuh 3 of Codename: Kids Next Door has this any time she gets power. The two times we've seen this is when gaining control of her father's thermostat turned her into a fiery demon that would even attack her own friends to stop them from turning it down and when using Santa's present delivery system caused her to direct every single present in the world to her house. However, both times she was secretly bitter over something. (Humorously in the former example, her father similarly becomes an icy demon as he turns the treehouse thermostat down; the adventure of getting him out of there is never shown.)
Numbuh 4 does this too, when he's made temporary leader while Numbuh 1 was away. He ends up declaring himself permanent temporary team leader and tries to build a giant "Clam Cannon" based on a sarcastic comment from Numbuh 5. (Humorously, not only does it work to stop an ambush by the DCFDTL, Numbuh 1 approves of the Clam Cannon idea when he gets back, but tells them they'll need to rework a good chunk of the device. Numbuhs 2, 3, and 5 instantly shake off the fatigue Numbuh 4 put them through and are eager to work all night again.)
American Dad! featured an episode where Steve became the school announcer, but the power went to his head, and caused him to believe whatever he said came true. Everyone who used the intercom in the episode eventually went mad with power. Everyone.
Even after they were on the intercom for just a few seconds.
Even Marvin Martian says "You're drunk with power!"
"Field Marshall" Phoebe in Hey Arnold! when she became hall monitor.
My Little Pony: Friendship Is Magic: In "Magic Duel", the Great and Powerful Trixie returns to Ponyville to challenge Twilight Sparkle, armed with an evil-looking amulet that boosts her power massively... at the cost of her mental stability. After soundly outclassing Twilight, she forcibly throws her out of town and places a magic barrier over the place to keep her out. Eventually the town has turned into a dark den full of sinister red banners and statues of Trixie and a permanent storm cloud keeping sunlight out; the mayor is locked in a cage, Twilight's friends are forced to do slave labor, and she's making Snips and Snails cart her around on a wagon without wheels, because she has decided that wheels are "untrustworthy". Once the amulet comes off, she loses her power boost but returns to her senses, and later apologizes for what she's done.
Most, if not all dictators and a great many absolute monarchs end up this way.
The Stanford Prison Experiment. Two groups of people, one group acting as the prisoners, the other acting as the prison guards. The experiment quickly got out of hand since the guards were becoming more violent and abusive (in the name of "trying to keep the prisoners in line"), and the prisoners either letting it happen to them, or fighting back with even more violence and abuse. Keep in mind that these were all just normal college students who willingly volunteered to be in this experiment.