The Apocalypse Brings Out the Best In People

In peacetime, certain characters are at best Shrinking Violets and, at worst, menaces to society. But when disaster strikes, they will take the lead, take control, be surprisingly effective, and maybe even be nicer than usual -- or if they aren't, at least they don't seem so different from everyone else. They will seem different if any Fridge Logic gets applied.

This sort of character is often forced into a Heroic Sacrifice or (for nastier peacetime examples) Redemption Equals Death. If the character does survive, and if things ever return to a semblance of normal, then they are as likely as not to return to what they had been before the disaster took place, whether anyone wants the jerk back or not.

When said apocalypse happens in the Bad Future, this trope leads to Future Badass.

This trope and its inversion are both Truth in Television.

Compare Machiavelli Was Wrong.

Examples may contain unhidden spoilers, so tread lightly.

Anime & Manga

 * Chad from Bleach.
 * In Stellvia of the Universe, a star going supernova devastates civilization. Humanity not only rebuilds, but creates a Utopia. It is also, however, implied that humanity would have ended up creating a Utopia regardless, only a bit later...
 * When the New Bloodline drove Tokyo to its knees in Majin Tantei Nougami Neuro, it was Da Chief Naohiro Usui (who up to this point was a complete dick) who lead the police and Tokyo to band together to resist him.
 * Future Badass Trunks, compared to regular Trunks.
 * One of the main characters in Violence Jack was a slacker, high-school kid was compeltely pampered by his mother and sisters. Then and he got to keep living alone, becoming a Badass and the leader of all orphan kids in Kanto.

Comic Books

 * The premise of Incorruptible. Notorious supervillain Max Damage turns over a new leaf when his archfoe the Plutonian goes insane and puts the entire world in jeopardy. The trope was eventually taken to its logical conclusion when Max thanked the Plutonian for going rogue, since it inspired Max to become a better person.

Fan Fiction

 * Shinji and Asuka in The Second Try. They're the last two people on Earth and have to fend for themselves, eventually getting past their laundry list of neuroses and becoming a pair of Badass Bookworms, as well as

Film

 * The main character's case for sparing humanity in the remake of The Day the Earth Stood Still.
 * The stuck up Ice Queen journalist in Deep Impact goes through this, defrosting including in front of her until then hated father, and ultimately
 * Harlan Ogilvy in the 2005 film adaptation of War of the Worlds.
 * Maruti from The Return of Hanuman is considered a naughty kid in the village. But when Rahu and Ketu tries to destruct the village, Maruti turns into Hanuman to beat them up. Because Hanuman is a Hindu God, all of the villagers worshipped him.
 * The title character of Shaun of the Dead, in part due to his familiarity with Survival Horror games.
 * Although it's ultimately prevented from happening, this trope is 's plan in the film Constantine.
 * Typically inverted in George Romero's Zombie films (X of the Dead). The Zombie Apocalypse always seems to bring out the worst in people, to the point of humans being their own worst enemy instead of cooperating to survive the undead onslaught.

Literature
"Solzhenitsyn: And how can one explain that certain unstable people found faith right there in the camp, that they were strengthened by it, and that they survived uncorrupted? And many more, scattered about unnoticed, came to their alloted turning point and made no mistake in their choice. Those who managed to see that things were not only bad for them, but even worse, even harder, for their neighbours. And all those who, under the threat of a penalty zone and a new term of imprisonment, refused to become stoolies?
 * The Last Survivors characters.
 * Neville Longbottom in Harry Potter and the Deathly Hallows.
 * Harold Lauder of The Stand. For a while, anyway. Larry Underwood is a more straightforward example, changing from a hedonistic rock star type to a pillar of The Free Zone's community.
 * S.M. Stirling's Emberverse series revolves around this. While it contains a very tragic portrayal of what would happen to society if all modern technology stopped working, quite a few genuinely "good" people rally survivors to them and keep them organized and safe under extraordinary circumstances.
 * Most characters in Alas, Babylon are examples of this after nuclear war irrupts between Russia and the USA. The main protagonist, Randy Bragg, goes from a lazy, failed politician living on his family's inheritance, to a strong and capable leader. Also, on a society-wide scale, the nuclear war causes an end to segregation, at least in the area where the main characters live.
 * In Alexandr Solzhenitsyn's history The Gulag Archipelago, a massive compilation of the horrors perpetrated by the Soviet Union upon its own people, there is a small amount of space given to the optimistic attitude that even the personal apocalypse of being arrested and sent to a work camp can still bring out good in people. Most prisoners relinquished their morals when they entered the camp and instead took up the aim of 'surviving at any price,' even if that price meant stealing the small daily bread allotted to another suffering prisoner. But there were indeed some people who avoided falling into this trap of despair and evil:

Solzhenitsyn: As soon as you have renounced that aim of 'surviving at any price,' and gone where the calm and simple people go--then imprisonment begins to transform your former character in an astonishing way. To transform it in a direction most unexpected of you. And it would seem that in this situation feelings of malice, the disturbance of being oppressed, aimless hate, irritability, and nervousness ought to multiply. But you yourself do not notice how, with the impalpable flow of time, slavery nurtures in you the offshoots of contradictory feelings.... You are ascending."


 * Most of the Americans in 1632 and its sequels are hillbillies from a small town in West Virginia, and had the town not been transported back in time to Germany during the Thirty Years War, they would probably have remained a group of working class miners and locals from a small town in the early 2000's. Once they come to terms with their new universe, their future knowledge base and cultural attitudes give them an edge that propells some of them to grand positions on the world stage, and many of them find personal fulfillment in surviving in their new world that they might never have achieved in their original timeline.
 * Norma in Fannie Flagg's small-town novels is a very anxious woman under normal circumstances, but when disaster hits she helps a lot of people partly because she can imagine the worst so vividly that she's prepared and ready to act.
 * In the Codex Alera series, the Vord invasion causes the otherwise scheming Anti Villain Attis Aquitaine (who has been an active villain for the rest of the series who only works with the protagonists against mutual enemies) to rise up and take command of Alera and lead the people as best he could. At the end, when
 * On a related note

Live Action TV

 * Most of the protagonists of Jericho undergo this with lead character Jake being one of the best examples.
 * G'Kar of Babylon 5 was an arrogant jerk when his people, the Narn, were on top. When the Centauri (aided by the Shadows) conquered and brutally oppressed the Narn homeworld, he evolved into a leader, a hero, and eventually, a prophet. Quiet Centauri aide Vir also discovered his inner hero after the conquest of Narn, using his position to smuggle a number of Narn to safety.
 * Londo gets worse at first, but then gets better when he realizes what working with the Shadows and Morden is doing to his people and to himself. He spends a good portion of the series working to mitigate the damage wrought by his earlier actions.
 * One episode of The Outer Limits has servant A Is cause an apocalypse (to the best of their ability) for the sole purpose of invoking this trope. It turns out the whole thing was set off by the opening scene, where the desk hologram sees an elderly woman collapse in front of her door, convulsing as she desperately tries to reach for her dropped medication. The hologram attempts to call her neighbors so they can come help but all of them are just mad at being bothered. The hologram realizes after she dies that his programming instructions to provide a social community living environment aren't being met if the tenants are hostile to the idea of even briefly seeing each other, and deliberately fries his systems to force the humans to cooperate in order to escape.
 * Summer Landsdown of Power Rangers RPM. A shallow Rich Bitch before the Robot War, she wandered alone through the devastated wasteland and saw her beloved butler die in her arms. By the time she got to the last haven of mankind, she was a Badass Biker Action Girl who truly cared for her fellow man, and quickly goes to the front lines as a power ranger. The series ends with the war, so we don't see if she regresses when she goes back to civilian life.

Video Games
That said, Lin's theory is supported by the fact that even after the apocalypse, there's still a war going on. And tyrants like Greyfield rise to power.
 * In Advance Wars: Days of Ruin, Brenner is very proud to see that what's left of humanity after the meteors hit have banded together to form small communities and even enforce rudimentary laws among themselves. Lin scoffs at the idea that this is a reflection on humanity's kindness, instead stating that it's nothing more than survival and that everyone involved is really just looking out for themselves.
 * Lampshaded by Alistair in Dragon Age: "You know, one good thing about the Blight is how it brings people together." Right after he was once again dragged into other people's petty feuds.
 * Groose from The Legend of Zelda Skyward Sword.
 * This is basically Paragon Shepard's view on the Reaper invasion in Mass Effect 3, in a nutshell. And given how many missions, War Assets, and side conversations involve old grudges laid aside, self-sacrifice for the cause, and just plain hope -- s/he's got a hell of a point.

Western Animation

 * Leon from Titan Maximum became the Sixth Ranger of the team in the time of need. He's still silent.

Real Life

 * While most certainly not the Apocalypse, the 9/11 attacks certainly banded up New Yorkers together to help firefighters and rescue workers during the aftermath.
 * Not exactly apocalypse, but it is often said that people are at their most united when they have something to fight against. This has unfortunately been exploited in war (e.g. many propaganda posters in WW 1 and WW 2 tried to get men to join the army by telling them they would have a great time with their mates in the army).
 * Sticking with WWII, the legendary "Dunkirk spirit" (volunteer rescuers) or "spirit of the Blitz" (Londoners) is an example of this trope.
 * Hell, take just about any war, disaster, or atrocity in history. Chances are, you'll find at least one shining example of humanity in the midst of it all, alongside with the exact opposite.