Characters in comic books shift allegiances all the time, but it’s almost never as dramatic as it was in Secret Empire, right? Secret Empire blew people’s minds when, in Captain America: Steve Rogers #1, the titular character announced “Hail Hydra,” letting everyone know that he was a sleeper agent, working for the Nazi-adjacent group, “Hydra.” Since then he’s taken over the country, S.H.I.E.L.D., and possibly soon will take over the world. It was a stunning revelation, but as long-time comic readers know, it’s not the first time a previously noble hero took a turn down the dark side.

RELATED: Road To Secret Empire: The 16 Most Heinous Things Hydra Cap Has Done (So Far)

Previously good characters turning into sinister villains is a long-beloved tradition in the annals of comic books. Sometimes it’s explained with hand-wave-y magic, or with brainwashing, or with other scientific reasons -- but sometimes it just turns out that hero you love broke bad. And sometimes, the changes don’t entirely go away. With that in mind, let's take a look at some of the best villain turns that have ever happened in comic book history. Prepare for whiplash because we're going to go through some serious twists.

*SPOILER WARNING. Spoilers abound for, well, all of comic history. Don’t say we didn’t warn you.*

15 INJUSTICE

15 INjustice

Injustice is, perhaps, the most popular tie-in video game comic ever made. The story deals with the lead-up to the video game Injustice: Gods Among Us, detailing a horrific world in which Superman -- after losing Lois Lane -- snapped, killed and took over the world. The only force that can team up against him is Batman and a handful of other human-level characters who, lucky enough, find pills that enable all of them -- including Alfred -- to take Superman on, one on one. Of course the comic is filled with the scattered remains of those who find out it’s not quite that simple.

One of the reasons this story works so well is because it takes place outside of continuity. Doing a story like Superman: Red Son or Injustice in continuity would be hard and leave a bitter taste in most people’s mouths. But doing it out of continuity? Then we get to have our super fun, super bright Superman, and also a dark, brooding Ubermensch. It’s basically Hannah Montana!

14 THUNDERBOLTS

14 Justice Like Lightning

Thunderbolts was an amazing comic about a brand-new superhero group who were actually a bunch of supervillains in disguise. The group debuted in a different comic and were slowly built up to be the replacement for The Avengers, who were gone at the time. This all would have worked out swimmingly if, in their first issue, it wasn't revealed that they were actually the Masters of Evil in disguise.

These weren’t a bunch of heroes no one had ever heard of before but a bunch of supervillains teaming up in an attempt to gain the public -- and S.H.I.E.L.D.’s -- trust before using it to accomplish their evil deeds. It was awesome, partially because it revealed some of the newest and most exciting superheroes as actually villains -- keeping it a secret up until the last page reveal of Thunderbolts.

13 SUPERIOR SPIDER-MAN

13 More Like Doc Hot Amiright

Superior Spider-Man is, bar none, the coolest Spider-Man story that doesn’t involve Stan Lee and Steve Ditko. It tells the tale of Spider-Man, dying, in the body of Doc Ock, who had stolen Peter’s body. When the story begins, no one knows that Doc Ock has taken over Spidey’s body. It takes -- admittedly -- not super long for the reader to find out, but that singular shock is so, so profound.

Plus, Doc Ock stays in Peter Parker’s body for, um, a very long time. And as he lives, he changed Parker’s life forever -- getting a doctorate, creating a company, and helping save the Universe. One of the reasons that Superior Spider-Man is one of the best face-heel turn characters is because eventually his hero side still wins out. He’s still a hero, even when he’s Doc Ock.

12 RUNAWAYS

12 PERFE Runaways

Runaways is about a bunch of children of rich Californians who discover that their parents are actually supervillains. The group of kids run away (get it?) and decide to fight back against their parents’ evil group (called The Pride). Eventually, it turns out that the Pride is operating on the orders of eldritch beings called The Gibborim. As the Runaways prepare to fight against the Gibborim for the fate of Earth, it turns out that one of the Runaways is secretly a mole for The Pride.

Making it all the worse, he was the leader of The Runaways the whole time. Yep, Alex Wilder turns out to have been working for his family in an attempt to destroy the very team he’s been supposedly leading. It’s a heart-breaking, stomach churning moment, made even worse by the fact that he dies shortly thereafter. We fall in love with him only to learn he’s evil. It’s like all of your high school relationships!

11 GREEN LANTERN: PARALLAX

Hal Jordan as Parallax

Parallax was the end result of The Death of Superman. After Coast City (Green Lantern’s home) gets utterly destroyed by an evil Cyborg Superman, he goes nuts and tries to recreate the entire city with his ring. Unfortunately, it doesn’t work, so he decides to become a space fascist to get more power, killing everyone who stands in his way, including the entire Green Lantern Corps. He renames himself Parallax and became DC's biggest bad since the Anti-Monitor!

But what truly throws this into completely awesome territory is the fact that, in attempting to retcon it, some of the coolest mythos of the entire DC Universe were invented. The yellow lantern entity Parallax came out as the reason for why Hal Jordan fell to evil, providing a foothold for his eventual (and awesome, thanks to Geoff Johns) "Rebirth." From there, it spiralled and we eventually ended up with dozens of different Lantern corps, as well as some of the coolest Lantern stories ever, including The Sinestro Corps War and Blackest Night.

10 SUPERBOY PRIME

10 Superboy Prime

Superboy Prime is, at this point, much more well-known for being an evil entity than a good one, but that's not hoe it began and ad the time, it was still an astoundingly surprising twist. See, Superman-Prime comes from an earth where superheroes exist only in comics. In other words, our earth, called Prime. He’s named Clark Kent by nerdy parents and becomes a big fan of comics; so basically, he's you, if your name was Clark Kent. Except, unlike you (probably), he has all of Superman’s powers.

Eventually, he finds his way into the mainstream DC Universe and fights alongside all of his heroes to save the Universe. He eventually winds up in a Paradise dimension to live forever… except he then goes mad and becomes a super powerful and super petulant villain, one who is stronger than basically any other DC villain, aside from perhaps the Anti-Monitor. Fortunately (or unfortunately, depending on your viewpoint), Superboy Prime might even be coming back soon.

9 WINTER SOLDIER

 

During the Cold War, there was a soldier who seemed to never get any older. He was behind dozens of horrifying events, but officially was nothing more than a rumor. When he came at S.H.I.E.L.D., working for a man who stole the Cosmic Cube, he fought against Captain America, who discovered who he really was. During World War II, Captain America had a young associate who fought alongside him named Bucky Barnes.

Eventually, a day came when Captain America fell into the ice… and Bucky Barnes apparently died. Cap would eventually come back to life and learned to adapt to this new, strange world. However, he still mourned his lost friend, the one who was there for him when he was young. Finding out that Bucky and The Winter Soldier were one in the same was both amazing and, at the time, incredibly controversial.

8 KID MIRACLE

8 Kid Miracle

Miracleman by Alan Moore is considered one of the best superhero comics ever made, and it's not hard to see why. Okay, well, it's not hard to see why now. For a long time, the books were out of print and everyone was fighting over the rights to the character. So go grab the books, read through them, and then come back. Or, you know, don't, since we're about to tell you what happened. Miracleman was a character that was basically Captain Marvel (Shazam, not Carol).

The comic was a dark, brutal tale, showing that all of Miracleman's younger sidekicks had died or been tortured... except one. Miracleman found that Kid Miracle was still alive... and super evil. Their fight led to destruction that had never been seen on page before. It was what led to Uber and The Ultimates and The Authority; the most destructive, horrifying event in comics. Kid Miracle destroyed, tortured, killed -- it's impossible to describe the brutality of the comic. It was a turning point, which is why his turn is one of the best around.

7 TERRA

terra

Ah, Terra. There's a lot to say about Terra. You could write essays, books, and deconstructions of what happened to her in the Teen Titans story, The Judas Contract. In short, Terra was a new Titan, one who had control over the Earth -- but it turned out she was working with Slade Wilson, Deathstroke, Teen Titans' archenemy. Oh, and she was sleeping with him, despite her being about 14.

Her turn was integral to her character and her story has been remembered, toyed with, and adapted ever since it was first created. It's controversial. It's dark. It's interesting. And, honestly, it might not have been a good idea. But Terra has stuck with us since then -- and her turn is the single lynchpin, while other plot elements from that time have fallen away. We'll always remember Terra's betrayal. And we'll always argue about whether or not she was a victim or a perpetrator.

6 OZYMANDIAS

Watchmen Quiz Ozymandias

Another Alan Moore joint, Watchmen is pretty much the perfect comic book to a lot of people; a book that deconstructs every superhero template you can imagine and puts them back together in the most interesting ways imaginable. At the end of Watchmen, you learn that the whole tale -- all of it -- was a small blip in Ozymandias' grand plan. To put it simply, he manipulated history and destroyed New York, all in an attempt to gain world peace.

He was a superhero... until he wasn't... unless you agree with him, in which case he was the ultimate superhero. He certainly thought he was, and that's what makes his turn great. His story wasn't necessary to all of comics, nor is he a particularly beloved character, but not many other villains have so expressly believed in themselves more than Ozymandias, making him truly tragic and his turn truly magic.

5 SUPERIOR IRON MAN

5 Superior Iron Man

Superior Iron Man was part of the fallout from the Axis event at Marvel comics, during which heroes and villains had their personalities inverted. Carnage became a hero, for example, while Tony Stark? Well, he became a much more realistic billionaire, weapons developer. After his change of heart, Tony goes to the West Coast and decides to "help" the people there by infecting everyone with a virus that made them appear beautiful and powerful, in an attempt to get them to make money and become slavish to his business empire.

The reason this comic is one of the best turns -- aside from his slick white costume -- is because you can so easily see Tony Stark becoming a villain. He's already had issues with boundaries and control given his alcoholism, but the turn he takes make him tumble into a downward spiral of addiction, abuse and evil. It's a great relapse for his character and an interesting look into what might happen if he fell. At the same time, though, we are glad it didn't last long.

4 ULTIMATE REED RICHARDS

4 The Maker

Back in the halcyon days of 2013, there was another full Marvel Universe, filled with its own heroes and villains. The best baddie was Ultimate Doom. He had many names; the one he goes by the most now is The Maker, but the most recognizable is Reed Richards. The point of the Ultimate Universe was that it was dark and realistic. It had wonderful heights, but horrifying lows. One of its first series was Ultimate Fantastic Four, telling the tales of the Fantastic Family beginning new adventures. However...

After a series of cataclysms, and Sue leaving him, Reed goes insane. He slowly starts attacking every person he knew and loved, becoming Ultimate Doom. He gets stranded in the Negative Zone and comes back, stronger than ever, creating a city in which one thousand of years pass in a day, growing his brain, and creating super advanced "children." He's one of the only villains from the Ultimate Universe to make it to Secret Wars' Battleworld and as of this writing, is the only Reed Richards that exists in the MU.

3 BATMAN

JLA-Tower-of-Babel-Batman

Batman brought down the Justice League in Tower of Babel. Sort of. See, the League gets taken down... and it's because of Batman. He has plans to take down every single member of the League, which of course get stolen and exploited by his greatest enemy, Ra's Al Ghul. While it's not entirely out of character for Bats to have these plans, seeing them used against the League hurts so much.

Of course, for them, it is a surprise. Batman, a member of DC's Trinity, is the one who brings them down, not one of their enemies. It's not a story that happens out of continuity, either. Batman, one of the founding members of the League, betrays them! Granted, it's not on purpose, but it's still a betrayal, knowing that one of the most trusted members had secretly been plotting the downfall of all the rest.

2 FUTURE FLASH

2 Future Flash

The best stories always involve heroes fighting a version of themselves. People have long drawn comparisons between Batman and the villains he fights. Same with The Flash, who fights a man whose power is to slow people down, and the Reverse-Flash, someone who has all his powers but none of his morals. But then there was one foe who was harder and more personal than any of the others -- The Future Flash.

Barry Allen from the future came back to kill The Flash before a horrible event came about. The idea of a more skilled hero morphing into a supervillain and then coming back to kill the less experienced version of himself is so, so, so cool. Plus, look at that costume! How is it not amazing? The story was even cool enough to get a (somewhat different) adaptation on The Flash.

1 ALEXANDER LUTHOR

1 Mazahs

Alexander Luthor Jr. is from Earth-Three and is one of the only heroes of that world. There, the heroes are villains and the villains are heroes. The Crime Syndicate -- a dark echo of the Justice League -- freaking rule. But Alexander Luthor keeps the small amount of free people alive, saving them, and being their hero. And then... there was Forever Evil.

Forever Evil reintroduced the Crime Syndicate, this time into the New 52, a world that was already incredibly dark. Here, Alexander Luthor was blind-folded and kept prisoner. The comic leads you to believe that, like in the older comics, he was a hero that could help defeat the Crime Syndicate -- that he was, perhaps, the one person who could stop them. But then, it turns out that this Alexander Luthor is the worst of all the villains -- he's Mazahs, the evil version of Shazam (aka Captain Marvel). The revelation that he's evil, that he's even worse, is such a dark moment in one of the darkest stories in the New 52, which frankly is really saying something.

What was your most memorable superhero heel turn? Let us know in the comments!