"Because he was such a nice, good person, he could play villains wholeheartedly. Whereas people who've got a dark side of their own, can't go for it a 100 percent because of not giving it away. Roger hadn't anything to give away, so he could do a 100 percent nasty."
A commercial for the business card company Vistaprint invokes this. The ad begins with a typical Scary Black Man standing in a rather intimidating pose, looking like a security guard or bouncer, and then it's revealed... he's a wedding planner, and is about as threatening as milquetoast.
Another ad for the same company shows an old man glaring into the camera, looking like he has a grudge against the world... only to pull back as he slips on a set of headphones, revealing he's a DJ and not nearly as unpleasant as he looked.
The entire premise of a series Walker's Crisps adverts features Gary Lineker, an ex-footballer famed for his friendliness a man who epitomised the spirit of the game in over a thousand top-level appearances for his club side and for England, and who was never booked once, stealing bags of crisps from children.
Anime and Manga
This is the entire premise of Detroit Metal City: The main character is a young farm boy who wants to be a sappy pop idol, moves to the big city to pursue that career, and discovers he can only get a job as the lead singer of a death metal band. He's perpetually terrified.
A scene in Perfect Blue has Mima playing someone up on stage who gets manhandled and raped by a rowdy crowd. Mid-scene, the director yells "Cut! Everyone freeze!" and the guy on top of her quietly stammers out, "I'm so sorry."
The main premise of Wreck-It Ralph revolves around this trope, as the way that characters act in their games doesn't necessarily reflect their actual personalities outside of gameplay.
Antagonists such as Bowser, Clyde, M. Bison, Kano and Dr. Robotnik are treated as this. When you see them in Bad-Guys Anonymous they are just nice people who play bad guys, yet tend to be treated like dirt.
Randall in Monsters, Inc. is revealed to be just this in the end-credit outtakes: an actor playing a bad guy. We also see that the dour, humorless character Roz is a real joker off-camera.
And an outtake at the end of A Bug's Life has scary grasshopper Thumper anxiously asking the director about the quality of his Ax-Crazy performance of mere moments before.
Both Hamm and Mr. Potato Head from Toy Story. Whenever Andy is playing with them, they're always cast as the bad guys.
And possibly EmperorZurg, who is actually evil because he always thinks that he is the real Zurg, much like the toy version of Buzz Lightyear constantly thinking that he is the real Buzz and not a toy.
For Toy Story 3 Dolly, one of Bonnie's toys. Whenever Bonnie is playing, she's always cast as the villain of her stories.
And since all of Andy's remaining toys now live in Bonnie's house, during playtime, Hamm, Mr. (and Mrs.) Potato Head, and Dolly will all be the villains.
Discussed in one issue of the Archie Comics. Reggie is booing and heckling a pro-wrestler and egging him on when the guy hurls insults back, knowing the guy can't do jack to him. So later when Reggie's car gets a flat and that same wrestler pulls over to help him out, Reggie is terrified until the guy explains what The Heel is in wrestling and that the whole point of his character is to be booed and heckled.
In Rocky III, Rocky Balboa agrees to a charity match with a massive pro-wrestler named Thunderlips, played by then known mostly only to wrestling fans Hulk Hogan. Rocky tries to goad Thunderlips into a friendly fun match but that soon leads to Rocky being tossed around the ring like a ragdoll, suplexed, back nearly broken over a knee, and finally tossed clear out of the ring well into the audience. After climbing back in the ring and delivering some bareknuckled damage of his own, the match is finally determined a draw and the after match interview reveals Thunderlips to be a pretty okay guy, congratulating Rocky on a good match and posing for pictures with his wife and kids, explaining his actions in the ring as "The name of the game." The final shot of the scene is a newspaper headline revealing that the charity match raised over 75,000 dollars for a local youth club.
The Wrestler, being a movie about Professional Wrestling played on this, since both Faces and Heels were portrayed as friendly towards each other throughout. One particularly impressive scene had the main character (Randy, a Face) discussing the "script" of his upcoming extreme rules match with his opponent, who was a polite and soft-spoken man (real-life wrestler Dylan Keith Summers, whose ring name is Necro Butcher in real life too!). The scene was threaded with scenes from said match; including once with the Heel stapling a five dollar note to his own forehead before going nuts on Randy with the staple gun. Preceding question: "How do you feel about staples?"
In a less extreme example, a similar scene with Randy's old 'nemesis' from The Eighties, the Ayatollah, showed him to be a quite pleasant and nice man. During the climactic fight, he also shows concern for Randy's health and ends up trying to persuade Randy to just go for the pin. Randy refuses.
Played with in Flann O'Brien's modernist novel At Swim-Two-Birds, where the main character of the book the protagonist is writing, Dermot Trellis, is writing a moralistic novel where all the characters are awful and sinful. A metatextual conceit portrays the fictional characters of Trellis' novel as actors he has hired. We then see what they're doing when off-duty from their jobs as terrible people - mostly having dinner parties, discussing Irish poetry, and being very nice to each other. They then start to rebel against Trellis forcing them to be evil, and as their tormenting their own creator gets more and more genuinely cruel, we start to see Trellis himself - ostensibly set up an unpleasant, self-righteous fool - become more and more sympathetic, pitiable and reasonable as the story mutates further, and we see that the protagonist is using him to portray a villain the same way he is portraying his own characters. Much of the point of this is focused on the narrator's complicated relationship with his uncle (with whom he lives), and his gradual realization that people have more than one side to them.
Live Action TV
Parodied on The Chaser's War On Everything. In a send-up of a government TV campaign against domestic violence, which showed still images of men with voiceovers about how they are violent towards women, actors complain that they appeared in the ads and now everyone they meet in real life thinks they hit their wives.
Voiceover: Appearing in Government Ads: Australia says "No."
Actually used for a moral lesson in a Mighty Morphin' Power RangersPSA. The actor who plays Bulk, one of the two "bullies" along with Skull, is actually a nice guy in real life.
You could say the actor rubbed off on the character who ends up starting a I Am Spartacus standoff to rescue the Power Rangers when they are powerless and the villains demand the city's population surrender them immediately.
The Munsters features an episode with a fictional Horror Host named "Zombo", who, to Eddie's disappointment, isn't a blood-thirsty ghoul outside of his television show. The actor playing Zombo is in fact disgusted with the character and the example he sets for children like Eddie.
Sgt. Carter of Hogan's Heroes is a nice, enthusiastic young man. He's also the best at impersonating angry German officers and Adolf Hitler.
When Heather Locklear appears on Muppets Tonight, the Muppets are terrified of her, fearing that she might be as bad as her character on Melrose Place. Heather assures them it's just an act, and that she's very nice in real life... an assurance that comes to naught when Heather eats some mood-altering snacks. In that same episode, Kermit the Frog plays a vicious monster in one sketch; "This is fun! I never get to play the bad guy!"
The final season of How I Met Your Mother has William Zabka in a recurring role playinghimself, and he's struggled with the fact that so many people are used to him playing the antagonist in movies that nearly everyone he encounters, up to and including his own mother, automatically boos him and throws stuff at him, even though he's nothing like that and actually a really nice guy.
In one episode of Newhart, guest Don Rickles's character is eventually revealed to be an example of this trope, in an obvious comment on Rickle's "real life" stage persona.
Larry Kubiak from Parker Lewis Can't Lose is one. Being a huge, somewhat dim kid in high-school, Kubiak plays up his size and meanness so others won't pick on him. However, he frequently helps the heroes, and is a decent guy at heart, provided you don't get between him and anything edible.
Name any baritone singer and the roles he's known for and you'll probably get this trope.
Same for mezzo-sopranos, to a lesser extent.
The general rule is 'the darker & heavier the voice, the meaner and nastier the villain.'
Going one further: Professional Wrestler characters can acquire "The Gift", which allows them to use Inspired abilities. These abilities require devotion to a higher power. Out of all the professional wrestlers in the book, the rudo is the only one with the Gift (and the power "The Binding"). He's literally a tool of God.
In Pokémon Black 2 and White 2, both Brycen and Sabrina play villains at least once in Pokéstar Studio movies, and while they're both The Stoic, they're certainly a lot nicer than their movie characters.
Will Powers of Ace Attorney plays the Steel Samurai on-screen, but off-screen he's very gentle, and one of the most normal clients in the series. To his dismay, he has to hide his face around children, as his monster-like face might scare away kids.
This is a very Informed Deformity, both because he's kind of craggy but not frightening to viewers by any stretch, and because in the second game he spends an entire awards ceremony around a little eight-year-old girl who doesn't appear to give a wet slap what he looks like.
Is this an informed deformity (to us)? Or does Mr. Powers actually think he's ugly? You decide.
Although the Steel Samurai is a hero, so it's more like a case of Tough Character Meek Actor.
In Umineko no Naku Koro ni, the Stakes of Purgatory are ruthless and very much capable of killing in cold blood. Behind the scenes, they're not so bad - we see Beelzebub and Battler playfully fighting over Ronove's baking early in Episode 4, and let's not get into them gushing and squeeing over cute little Sakutaro.
Certain online porn parody webcomics revolves about actors playing video game characters and main cast is made of guys who plays tiny-veiled copies ofSoul Calibur characters. Actors playing the meanest villains (Nightmare's and Astaroth's counterparts) are quite decent guys.
Lucy in YU+ME: dream is a sweet young woman who's nice to the protagonists, even if her motivations might be a little more complicated than just that. She's also a dream actress. What character did she play? Sarah, Fiona's former childhood friend and current enemy, in Fiona's dream. The fact that Lucy is a different person than the character she plays is a bit of a surprise.
The VeggieTales short "Where's God When I'm S-s-scared?" reveals that the actor playing FrankenCelery in a horror movie that scared Junior Asparagus is actually a pretty nice guy. His name is Phil Winklestein, and he's from Toledo Ohio.
Notably, they take over the House in one of the direct-to-video films, but it doesn't really last for long. The film was more of a compilation of shorts, so when the villains did take over the club, they didn't really change it much aside from having to keep kicking out Mickey and the gang.
Donald Duck himself is this in the eyes of his voice actor, Clarence Nash; on his later days, he used to carry a Donald puppet everywhere to play ventriloquism with, and he would make him say that he never got mad; he was merely an actor.
Similarly, a Bonkers comic in Disney Adventures had Monstro from Pinocchio as a long-out-of-work Toon actor who was actually pretty friendly (albeit destructive due to his size) off the set.
Family Guy - Chris' idol, Marilyn Manson, is revealed to be nothing like his stage persona and encourages Chris to not be a jerk towards his family just because he's gotten into rock music.
From the "Hannah Banana" episode:
Evil Monkey: I mean, Sarah Silverman is just one of the most wonderful people you'll ever meet.
Peter: Aw, that's so good to hear. I want to like her. She's so funny, I want her to also be nice.
In a related example, on ''Clone High", Marilyn Manson sings an insanely catchy Broadwayesque tune mostly about the importance of eating properly and paying attention to the food pyramid.
On The Critic, Jay got threats from an action star he had panned. He corners Jay in an alley, and just when it looks like it's the end, the actor reveals that he's really a nice guy, and only acts mean in his movies, and the threatening was just an attempt to prove that he reallycanact.
In the Hey Arnold! episode "Eugene, Eugene!", Arnold performs as the Big Bad of the titular play. This is a kid who has helped Mr. Hyunh reunite with his long-lost daughter after the two were separated during the Vietnam War.
And, despite Mr. Leichliter's coaching, he's still pretty awful at it, mostly out at protest at the play's morbid new ending.
Zigzagged but Justified with Angry Jack, a one-shot character in one episode of Sponge Bob Square Pants when Spongebob accidentally breaks Gary's shell and goes off to buy him another shell from "Angry Jack's Shell Emporium. At first, he is kind enough to let Spongebob accidentally break one shell without repercussions when trying to find the right shell size for Gary, but the episode's running gag of Spongebob's clumsinesscausing him to break EVERY shell at the Emporium ultimately causes him to revert to his "Angry Jack" persona, where he angrily forces Spongebob to repay him for the every single shell he broke.
Invoked on Phineas and Ferb, when Candace babysits her boyfriend Jeremy's little sister Susie in one episode. Susie is a holy terror to Candace normally, meaning that the teenager is terrified of this sitting job... only to find out that Susie is actually a pretty sweet kid. She explains to Candace that making her look stupid is something she does to control her brother (Susie has an almost disturbing case of Big Brother Worship combined with Clingy Jealous Girl), but since he's not on hand, "I'm off the clock."