'Allo 'Allo!: Essentially, any Nazi character in a lighthearted series could be considered this way, therefore implicitly being given a Villainy Discretion Shot. For example, Herr Flick of this show is the kind of character who, in a serious work, would be the Torture Technician, but is a very funny and likable parody of the stock "Hollywood Nazi" Secret Police officer. "You do have a soft side, Herr Flick!" "Yes, I almost failed my Gestapo exam because of it."
American Horror Story: Hotel: March. He's a remarkably genial fellow, even when slaughtering scores of innocent people. He mentored some of the most infamous serial killers in American history and has no redeeming qualities despite his sophisticated way of acting.
Andor: Dr. Gorst seems a rather personable fellow despite the unpleasant nature of his work and even gives Bix a friendly wave when Dedra introduces him. But he never shows any empathy for any of the suffering he causes his victims and seems to enjoy what he does. He smirks as he describes the Final Solution against the Dizonites and tortures Paak and Bix speechless and with a Thousand-Yard Stare.
Lyndysty from "Sic Transit Vir". She is a charming, sweet, and beautiful little Centauri, delighted to be engaged to Vir Cotto, and she personally put to death hundreds of Narns.
Alfred Bester, the resident Magnificent Bastard, is almost always polite and affable-seeming, though he can pour on the snark when he wants to. However, "seeming" is the key word here. Anyone with any experience of normal human interaction can see exactly how flimsy the facade is, and how broken and possibly sociopathic the person underneath is.
The titular hitman's handler Monroe Fuches from Barry. He's friendly, charming, and comes off like a fun-loving uncle all the while being a ruthless bottom-feeder who manipulated Barry - his surrogate nephew - into a life of crime.
The Brother Cavil model (the Ones) of Cylon display this sort of behaviour. Cavil, despite being depicted as the most out-and-out evil of the Cylons (perhaps the only one), is continually making snarky asides and hilarious observations about his fellow Cylons and humanity. This was even brought up by one of the others when he cracked a joke after having been shot on the orders of the speaker.
Natalie (a Six): Is there anything that isn't fodder for a joke with you, or is that really how you see our very existence, as some sort of nihilistic punchline? Cavil: Nihilistic punchline, I like that. But quite honestly, I'm feeling very serious. Getting riddled with bullets affects me that way.
Also this exchange, which occurred before we found out:
Chief Tyrol: How do you know I'm not a Cylon? Cavil: Well, because I'm a Cylon and I've never seen you at any of the meetings.
It gets even funnier when we find out Tyrol is a Cylon, but neither he nor the "regular" Cylons, aside from Cavil who wanted the Final Five to not know they were Cylons, knew it. Even better when you realise that there were Cylon meetings happening aboard Galactica. Yes. He just admitted to being a Cylon and meeting other Cylons and got away with it!
Herrick would seem to fit. In the first episode, he spends the first half of his introductory scene making nice with the hospital staff, and the second half talking about world domination and the hypothetical idea of turning terminally ill children into vampires. This is highlighted in the season finale when we see that he turned that mousy cafeteria worker, who is apparently now his lover.
In a later season, he resurfaces with amnesia, and Nina takes the opportunity to take him in and try to teach him to live a better life. When he regains his memories, he threatens Nina with a knife, and then calms her down, and says that he's very tempted to spare her for taking care of him and protecting him. Then, he stabs her anyway so people wouldn't think he went soft.
The historical gangster Arnold Rothstein is a good example of this, as a contrast to the Affably EvilVillain Protagonist Nucky. Rothstein is cold, ruthless, and amoral, but has a polite and somewhat charming manner, and gets his fair share of good lines.
Rodrigo is somewhat Faux Affably Evil as well. He cares about his family, but with most other people he's figuring out how to manipulate and deceive them and is only polite as long as he has to be. (He also threatened to excommunicate a city.) However, particularly in Season 2, Rodrigo's loyalty to the city and people of Rome is very sincere, and when he finds out that the cardinal responsible for charity has three palaces while the peasants starve, he is genuinely disgusted and tries to improve Rome for the benefit of the commoners rather than just himself. While it is true that he drops the mask of civility with people he needs to bully and manipulate, he is generally quite nice to people unless there is some real benefit to being nasty, and he never indulges in wanton cruelty with anyone who hasn't wronged him first. Rodrigo is a rare character who is both genuinely Affably Evil as well as Faux Affably Evil, depending on who he's dealing with at any given time.
Walter, by Season 5, has become this, especially around Skyler where even the lines meant to sound loving sound more like a kidnapper speaking to his hostage, and just about everything he says to other people, including his partner, Jesse, and even his own son, is nothing but manipulation to achieve his own ends.
Gus Fring qualifies as well. He's unfailingly polite, proper, and generous with those he trusts. He'll also personally cut your throat if he thinks it's necessary. It's left a bit ambiguous as to whether he's actually willing to have children killed, but he's certainly willing to make the threat.
Better Call Saul introduces Lalo Salamanca. From his first scene, he's cheerful, gregarious, and complimentary, but everyone around him seems petrified of him nonetheless. He quickly shows himself to be as Ax-Crazy as the rest of the Salamancas, fondly reminiscing with Hector about beating a hotelier to death and burning his business to the ground.
Spike before getting chipped: he carried a casual and personable demeanor to his foes, but only as far as it could be used to intimidate them. Comparing him with The Mayor is a good object lesson in the differences between the Faux Affably Evil and the Affably Evil.
Angelus can occasionally be shown with a seemingly friendly and understanding approach (much like as Angel). The fact that most of it isn't really genuine at all, not to mention that later on, it could also be a reminiscence of how he is when he has a soul which he might be deceptively using to his advantage makes it all the more terrifying.
Glory's a pretty good example of this too. She's actually rather funny and acts affably toward the Scooby Gang...while she's torturing them and draining their sanity. She's even rather civil to Dawn, shortly before she attempts to ritually sacrifice her.
The First Evil is sometimes this, depending on who it happens to be at any given time.
Vampire Xander. It seems that even becoming a soulless monster will not deter Xander from being one of the biggest examples of Deadpan Snarker ever.
Sahjhan is a witty demon who spends a good amount of time making jokes. He also lives for chaos and feeds on violence.
Sahjan: I flitted back and forth through time, changed a vision here, rewrote a prophecy there...flitted in a manly way.
Nathan Reed, Lindsey and Lilah's superior at Evil, Inc. Wolfram & Hart. Unlike Affably Evil Holland Manners, Nathan doesn't really care if Angel kills Lindsey or Lilah, because that would actually serve the firm's plan to make Angel evil.
Adam is another example. His voice rarely loses its calm tone even as he's plotting the murder of everyone around him. In one episode, he gets a nest of vampires on his side by calmly discussing what vampires fear: "Sunlight, stakes..." *casually rips off one of their heads* "It is my understanding that decapitation works as well. Death. Being immortal, you fear it more than those to whom it comes naturally".
The Gentlemen. Sure, they're nice to each other, but they use the same politeness to lure out their victims.
Larry Sizemore is a truly charming guy. If you met him at a party, you'd probably find him quite entertaining. Right up until he knifed you or poisoned you because he was paid to, because you were in his way, or just because he felt like it.
There's also Vaughn, Michael's handler in Season 4. He puts a lot of effort into the pretense of being a nice guy. He convinces Michael to work with him against worse people, tries to claim that other people from the Organization were just bad apples, he's always polite and doesn't seem to take offense to Michael going against him or even Michael kicking him out into a raging hurricane. But in the Season 4 finale, he abruptly drops any pretense of being affable. Note that 10 seconds before this, he was cheerfully inviting Michael out for drinks with a smile on his face:
Carla, Michael's handler in Season 2 and Vaughn's "predecessor", pulled something similar, always greeting Michael with a smile and maintaining a polite, albeit snarky demeanor, even offering aid in the form of cash or manpower at times. Unlike Vaughn, Carla's politeness only extends so far and often comes packaged with subtle and not-so-subtle threats to Michael about the fate of himself and his friends and family if he doesn't do what she wants. By the end, she was ready to blow up Michael with C4 had Fi not put a bullet through her abdomen.
Tyler Brennen is perhaps the show's best embodiment of this trope.
Choujuu Sentai Liveman: Great Professor Bias seems like a pretty friendly guy for a Big Bad; he's a Benevolent Boss who offers advice and encouragement to his students/executives, and even when he scolds them, it's in the name of getting them to do better rather than a genuine Bad Boss moment. Then we learn he cares nothing for his students at all, and is just manipulating them into becoming candidates for his Fountain of Youth to give him immortality.
Raúl is quite a good liar hiding his anonymous identity as the hacker...until SofÃa figured it out.
Pablo also falls for this trope, as he progressively starts losing his cool after being exposed as both a complete jerk and an unfaithful boyfriend to Isabela, causing him to become more violent, vengeful, and less sympathetic by the second season, wishing for nothing more than getting revenge on Raúl for his actions as the hacker that brought out his darker side.
Dark Shadows: Barnabas Collins. Part of the fun with Barnabas was the Dramatic Irony between everyone believing him to be a perfect gentleman while the audience knew that he was lying through his teeth.
While the Master varies Depending on the Writer and/or actor, one of the constant traits in their psychopathy is the ability to be charming and polite one moment, then ruthless and brutal the next, switching on a whim. Nowhere is this more evident than in their interactions with the Doctor, particularly the Roger Delgado incarnation, which would often be quite pleasant if one ignored how he would invariably be discussing his plans to cause widespread death and destruction.
"The Long Game": The Editor (played by Simon Pegg) initially seems polite, but quickly reveals himself to have a very twisted sense of humour.
"School Reunion": Mr. Finch, the leader of a group of murderous aliens trying to become gods, is always incredibly polite and charming. Even as he's planning to eat orphans, or have his brethren eat the Doctor's friends. However, he does seem genuine in his desire to have the Doctor join him, if slightly annoyed when the Doctor turns him down.
"The Time of Angels"/"Flesh and Stone": Angel Bob is unfailingly polite. It's explicitly stated to be doing this in order to anger the Doctor, but if you didn't know that, it almost comes across as the Angel being Innocently Insensitive.
"Amy's Choice": The Dream Lord acts like this towards the Doctor and Rory, having so much fun with his different costumes. Notably, in a piece of foreshadowing, he is genuinely Affably Evil towards Amy, who is never insulted like the others.
Madame Kovarian puts on a pleasant façade, but isn't very good at it, so she just comes off as smarmy, slimy, and insincere.
"Asylum of the Daleks": The Dalek Prime Minister, notable for having a bit more personality than the rank and file, is no less sinister for it, and his interactions with the Doctor are oozing with polite creepiness. And he enjoys it.
Count Scarlioni in "City of Death" spends an entire scene trading witty banter with the Doctor, even adding to his order that his Battle Butler lock them in the cellar by commenting that he'd "hate to lose contact with such fascinating people". The charming exterior is a front, however; underneath it all, he's entirely willing to not only wipe out humanity, but change history so that it never existed to begin with, if it gets him what he wants.
Dollhouse: Joss Whedon seems to like this trope. Alpha is likewise highly entertaining despite being unquestionably monstrous.
Dracula in Dracula (2020) can appear calm and well-mannered, but the slightest drop of blood causes his true, animalistic self to emerge.
The Escape Artist: Liam Foyle is a soft-spoken individual, who is mostly polite. However, he's not a pleasant person and he can easily drop the mask when he wants to. He shows he's fully aware of it during a few exchanges with Will.
Leland Townsend. By all accounts, he is a nice, kindly person in front of the judge or DA...but in front of David and Kristen, that nice facade drops and he taunts them with just how evil he really is. Specifically, he will taunt Kristen with passages from her therapy sessions that he stole.
Nurse Linda "Plague" Bloch mostly maintains her friendly facade, even as she's abusing black patients under her care (and it's implies she eventually kills them). The mask slips when she's thwarted.
The Family: Doug Anderson, aka the Pock-Marked Man (as he's listed in the credits). He's a friendly, charming man who no one would ever imagine is a serial kidnapper and rapist of children. Naturally, that helps in luring his victims.
The Following: Joe Carroll often acts like a doddering former literature professor/author who's affable, a loving father figure to his family, and enjoys tweaking main character Ryan Hardy with teasing barbs. The reason why he's no longer a literature professor is that he was revealed to be a serial killer, his "family" is a literal death-worshiping cult of fellow serial killers, and Ryan Hardy is a former FBI agent whose life he's trying to make a living hell. Every second he acts Affably Evil is all the creepier for how much the show emphasizes how bad he is.
Ser Jaime Lannister, who spends most of the time smiling, making self-deprecating jokes, and retaining his dignity in bad situations, and the remainder of it ruthlessly killing anyone, from children to his own distant cousins, who 'was in my way'. As the series progresses (and particularly in the books), Jaime is given more Character Development and becomes more of an overgrown jock who has never really properly grown up, but who is slavishly loyal to those few people he does love, namely Cersei and Tyrion. As the series progresses, his affability seems more and more to do with his hurt ego, and his attempt to injure Bran was more of a last-ditch attempt to protect his sister/lover, who would have been killed along with her children if their affair had been caught by the king. He's still not heroic, but he's not a card-carrying villain, either.
A much clearer example is Lord Petyr Baelish a.k.a "Littlefinger". Soft-spoken, charming, and polite, and openly admits he's untrustworthy, a combination he uses to further his schemes and lull his targets. He has all that Snark-to-Snark Combat with Varys, and he gives Ros to Joffery to have fun with. He also quickly betrays those he offers to help, like Ned Stark.
Ramsay Snow often comes across as friendly and playful, even gentlemanly around Walda and Locke, but it's clear that there isn't a single atom of genuine affability in the performance — especially when he is rather playful and jocular while torturing Theon Greyjoy and playing his hunting games, much like a cat playing with its prey.
Roose Bolton (Ramsay's father) can act as calm, polite, and accommodating as he wants; it doesn't hide the fact that he's only slightly less of a sociopath than his son.
Locke maintains a rather friendly, casual attitude with his men, whether that involves leading them in a song or setting out the order in which they'll take turns to gang-rape a captive. He also has a nice chat with Jaime, negotiating about how he can ransom him and Brienne, while Brienne is screaming in the background as Locke's men prepare to rape her. He then drags Brienne back so he can ransom her, and tells Jaime that he can have some nice hot partridge and a good night's sleep. He then cuts off Jaime's hand. After he returns to the Dreadfort, it turns out he's quite friendly with Ramsay, likely to no one's surprise. He also pretends to befriend Jon, making a good impression on Jon by lying that he was a game warden from the Stormlands who had opted to take the Black after he was forced to hunt illegal game to feed his kids. He effortlessly integrates himself as a new Watch recruit and volunteers to help Jon on a dangerous mission so he can betray him.
Myranda is all sweetness and light when talking to Sansa, but it's entirely an act.
Lord Tywin Lannister has shades of this in his negotiations with Olenna. He puts on a polite facade but it's not enough to hide his fury over how the Tyrells tried to marry Sansa behind his back (from his perspective).
Queen Cersei Lannister can pretend, and at rare moments her beauty and charm allow her to come across as decent. It's what fools Sansa for so long.
In the first season, King Joffrey Baratheon at least makes an effort to appear a charming noble, but once the crown is on he doesn't care to pretend anymore. When he does start to pretend, it's an indication he's about to do something horrible. For instance, when speaking politely to Ser Dontos, he tells him to have as much wine as he likes — because he plans to drown him in it.
King Euron Greyjoy is all smile and wit whilst murdering everyone in his way.
Inverted with the Hound. He actually pretends to be a Card-Carrying Villain who doesn't have any real goodness or emotions, but the reality is quite the opposite.
Green Wing: It's all but stated that, of all people, Dr. Angela Hunter is this. This Clip sums it up.
Hell on Wheels: The Swede. Sure he'll put on a good show and ham it up for audiences from time to time. But there hasn't been a character yet that he hasn't snitched about, knocked their tent down, tried to get hanged, or stabbed in the face with a fork.
Heroes: Sylar, the smirking, hero-slaying, brain-stealing supervillain. He really enjoys playing nice and polite before he straight up wreaks havoc on his victims.
Hightown: Frankie Cuevas Sr. always acts friendly, even to his enemies, but it's clearly false, with an obvious undercurrent of menace ever present.
Himmelsdalen: Carol at first seems like a nice, laidback guy. Then it turns out he's a leader among the patients who is implied to be a crime boss on the outside who's continued his ways with the same brutality. He's always polite and genteel to others, but it's clearly insincere.
Homicide: Life on the Street: Luther Mahoney, one of the few recurring villains. He's a drug lord who poses as a community activist, and at first, his affable demeanor is all part of his Villain with Good Publicity facade. After a while, though, he's clearly doing it just to mock and enrage the detectives, rubbing their noses in the fact that they can't prove he's a child-murderer, rather than the lovable local hero he says he is.
Vera plays up the act of being the perfect Housemother...but is ruthless in her efforts to get the Mask of Anubis for Rufus.
Miss Denby takes it to a higher level. She seems like the perfect teacher but is a skilled Manipulative Bastard who keeps her stepsister locked up, makes subtle threats towards Sibuna, and will hurt anyone to get what she wants- and was a whole lot more successful than Vera.
Jekyll: Benjamin affects mannerisms more appropriate for a goofy used car salesman than the kind of guy who buys a zoo just so he can throw a child into the lion pit.
Kingdom Adventure: Zordock is almost always an angry Card-Carrying Villain, but once in a while he'll adopt this attitude temporarily to flatter a minion or attempt to trick a hero. It never takes long for him to revert to his usual self, though.
Anthony Cooper, Locke's father. He gives off the impression of being polite, charming, and very fatherly, giving Locke the relationship he always wanted. But beneath it he is a thoroughly unrepentant, sociopathic monster who couldn't care less about the innumerable lives he has destroyed. His crimes include scamming countless people out of their money including Sawyer's parents leading to their deaths, murdering a young man who correctly identified him as a con artist, taking John's kidney and severing all ties with him, and pushing John out of a building, resulting in his paralysis. And he does it all with a sadistic grin and a charming word.
Martin Keamy attempts to show to both Ben and Sayid on two different occasions that he's Affably Evil, but neither of them falls for it and sees him as the completely unreasonable monster that he is.
MADtv (1995): Kim Jong Il. He hosts a talk show, where he seems like a charismatic, energetic host, if not for the fact that he jokes about his atrocities, and will kill people in his audience if they don't applaud his jokes.
Dale "The Whale" Biederbeck from Monk is a disgustingly fat financier and crime lord. Though confined to his bed due to his massive size, he acts polite, genial, and downright pleasant at times. However, all of his episodes reveal that this "kind" attitude is a front — he's actually a cold, ruthless monster who, if he doesn't get his way, breaks down and starts screaming threats.
Moses Jones: Matthias Mutukula from this BBC miniseries, who is an African warlord-in-exile. Usually polite and well-spoken, especially towards people he needs something from, but it only takes one wrong word for his pleasantries to become laced with threats. Threats he has no qualms about carrying out, such as having a restaurateur's teeth smashed in with a claw-hammer after the police speak with her. Then there's all the standard African Warlord atrocities he committed back when he was in power.
Neverwhere: Croup and Vandemar. Croup lampshades this trope moments before stalking and killing the Marquis de Carabas.
Croup: You find us funny, Messire Marquis, do you not? A source of amusement. Is that not so? With our pretty clothes, and our convoluted circumlocutions— Vandemar: I haven't got a circumlo— Croup: —and our little silliness of manner and behavior. And perhaps we are funny. But you must never imagine that just because something is funny, Messire Marquis, it is not also dangerous.
Cora. She does everything she possibly can to corrupt her daughter and make her life miserable, all while claiming to do what she does out of love. Rumplestiltskin and Regina tend to this persona in their more calmly and sadistically evil moments, as well.
Also, Zelena in her Storybrooke persona. She absolutely oozes friendliness and good cheer. Made really creepy by the fact that while the audience knows who she is, the rest of the characters don't and are easily taken in. Well played, Zelena. Well played.
Hades comes across as a Man of Wealth and Taste who is never seen raising his voice above his normal calm tone. He also takes great pleasure in torturing Hook and depriving the souls of the Underworld of hope and the ability to move on. And that relationship he has with Zelena? All an act to be able to leave the Underworld and gain more power
Orphan Black: Leader of Topside and self-aware clone Rachel Duncan is the definition of Faux Affably Evil. Although some may argue that she was attempting to be their friends, thus making her Affably Evil in her first few appearances, by Season 2, she shows little interest in their arguments. She holds the most power at DYAD by then and is able to pull strings wherever she needs – thus, she ends up kidnapping the protagonist's kid more than once. By Season 3, however, it seems she's on the verge of a Villainous Breakdown.
"It's foolish to spare you, but you raised me. Nurture prevails."
Hank Johanssen, leader of the Proletheans, always maintains a friendly demeanor, even when committing Cold-Blooded Torture against his own daughter.
Corbell Pickett carries himself like a charming Southern Gentleman and adopts a fatherly demeanour when talking to a bunch of his goons in the first episode... Right before smashing their leader's head into a glass because they've not been selling enough drugs for his liking and let themselves get intimidated by Conner.
Aelita's warning to Flynne about Dr Cherise Nuland in the first episode wasn't exactly wrong. She has immaculate manners but will become immensely menacing at the drop of a hat, and anyone who crosses her tends to have very little time left to live.
Person of Interest: Root, who likes to chat casually with people and torture them at the same time.
Psych: Mr. Yin. Even when he's trying to kill Shawn, Gus, and Juliet, he does so in a way that makes it seem like he's just trying to help you out but that polite demeanour covers up what a total sociopath that he is.
Reaper: Satan. He's evil, but he's just so cheerful about it that you have to love him. Until you disappoint him.
Victoria Grayson: Understand something Lydia: Every time I smile at you across the room or we run into each other at a luncheon or I welcome you into my home? Let that smile be a reminder of just how much I despise you. And every time I hug you? The warmth you feel is my hatred burning through.
Every single militia member, except for Major Tom Neville, is this. Captain Jeremy Baker in "No Quarter" acts like he's your best pal...but he certainly doesn't hesitate to send loads of soldiers to get shot by a sniper rifle. Sergeant Will Strausser acts so polite, but this sociopath is a complete monster who has no qualms about rape, which is what he tried to do to Rachel Matheson in "Nobody's Fault But Mine". Sebastian "Bass" Monroe takes the cake in this trope though, like when in "Clue" he tried treating Nora Clayton to dinner...and when she tried to kill him, he sent her off to be tortured for 21 straight days, and actually says that she should remember that he tried asking her nicely.
Drexel in "Sex and Drugs" qualifies. The first thing he does is to put a gun to Miles Matheson's head, pull the trigger, and then laugh his head off and claim that it was just a joke when it turns out that the gun isn't loaded. He tries to act like he's such a gracious and polite host, but he's actually violent, sadistic, sociopathic, Ax-Crazy, and politically incorrect. He is also a drug lord who deals in heroin.
Robin Hood: The Sheriff of Nottingham in the BBC series kind of fits this, being a Smug Snake with an extremely cruel sense of humor, yet hard to loathe given the humorous way he goes about his crimes. Notably, his insults against Robin generally are accurate in identifying unpleasant aspects of his character, and similarly, the Sheriff is very effective in mocking his humorless and angsty Dragon Guy of Gisborne.
Played straight with Detective Vic Mackey. Much is made toward the fact that over the course of the series, all of the police officers in the Farmington District Precinct turn a blind eye towards Vic's evil, largely because of his charisma, leadership skills, and fratboy humor. Even the ones who know Vic is a monster who shot a fellow police officer often fall victim to the spell, to such an extent that Claudette Wyms (Vic's "arch enemy") fires her hand-picked, 100% non-dirty cop replacement because he was too squeaky clean.
Armadillo Quintero from Season 2 seems friendly and laid-back at first, but in reality, he's a ruthless killer and rapist.
Antwon Mitchell from Season 4. The infamous scene where he kills a young girl to blackmail Shane Vendrell with the crime after Shane gets all uppity towards Antwon showcases actor Anthony Anderson's ability to mix unrelenting sadism with a sly sense of humor, as he humiliates Shane with his cruel actions.
Sons of Anarchy: Ethan Zobell, the charming, nattily dressed Neo-Nazi businessman. Politely attending a business meeting one day, ordering a woman raped the next.
The Sopranos: Tony Soprano zigzags between this and Affably Evil. He can be genuinely friendly and does make an effort to look out for those he cares about, but he gradually loses any real redeeming qualities. He will often act friendly to those he is just about to do something horrible to, like Jackie Jr and Phil Leotardo, just to taunt them. This is mostly relegated to people who piss him off, but Tony clearly gets a kick out of it.
Stargate Atlantis: Most Wraith that even bother dealing with humans fall into this, such as the Wraith Keeper from the premiere and the Wicked Cultured Wraith from the episode "Condemned". They'll make a token effort at fake pleasantries, but never let the humans forget that they're talking to a space vampire who would love to have them for lunch.
Star Trek: The Original Series: The episode "Plato's Stepchildren" has Parmen, leader of the Platonians. He passes himself off as an enlightened student of Plato, when he's really just a sadistic coward who delights in torturing his servant Alexander and mind-raping his "guests".
Garak is a rare example of a Faux Affably Evil character on the side of the heroes. However, his Enemy Mines eventually turn him into more of an Affably Evil character, and eventually into an outright Anti-Hero. He's more Affably Evil when we first meet him, his Faux Affably Evil days having occurred off-screen before the series starts.
Gul Dukat is a straight example. Because of their different values, most Cardassians are Affably Evil. However, Gul Dukat lacks the selflessness of most Cardassians. Whereas most Cardassians do what they do for the greater benefit of Cardassia, Dukat only cares about himself, taking his narcissism to hallucinatory and Ax-Crazy levels towards the end.
Gul Dukat may have become this by the end, but he was genuinely troubled by some of the terrible things he did to the Bajoran people and had to construct elaborate Well-Intentioned Extremist justifications for his actions to make himself okay with them. And he did have a great deal of fondness for both his half-Cardassianbastard daughter and main protagonist Benjamin Sisko. At least at first, much of his affability was probably genuine. Then "Waltz" happened...
The Female Changeling maintains a facade of civility, but it does a poor job of concealing her hatred of solids. When Garak asks her if there were any survivors of the Cardassian-Romulan attack on the Changeling homeworld, she flatly stated that they were all dead and she was planning on genociding the Cardassian people in revenge. She then politely asked if that answered his question.
Star Trek: Voyager: Kurros, the chipper dealmaker played by Jason Alexander in "Think Tank". He offers protection from a race of bounty hunters that are after Voyager, and a number of other services, asking in return only the chance to examine Seven of Nine's Borg implants. Except that he has no intention of returning Seven. And guess who took out the bounty in the first place?
Logan Roy from Succession can be quite charming when it suits him, but he'll quickly resort to bullying and stunning cruelty the second he faces any opposition.
Alastair, aka "Picasso with a Razor", loves to smile and chat up his victims as he's carving them up. He also inverts the trope in the episode "On the Head of a Pin", when he becomes Dean's torturee and spends the whole time dispensing advice, commenting on Dean's technique, or reminiscing about the good ol' days back in Hell, when he apprenticed Dean in the arts of mutilating people.
Lucifer is another prime example. Apparently, being locked in a cage in Hell for a few millennia works up an appetite for conversation. He treats Sam with affection, and never insults his victims or even raises his voice. But, despite his charm, he's squarely in the Faux Affably Evil camp because...well...he's the devil. In the Season 5 finale, "Swan Song", Dean finally manages to annoy him too much. He drops the act and shows just how affable he really is.
Crowley is presented as an Affably EvilNoble Demon in Season 5, but Season 6 reveals that he's more Faux Affably Evil, as he starts getting more and more into torture. He's obsessed with bargains and won't break a deal (as befits his "King of the Crossroads" status) but will take on any persona which will get the job done.
Dick Roman, the leader of the Leviathans. Having stolen the identity of a billionaire businessman, he likes to talk in a friendly, forward-thinking, businessmanlike fashion while planning the enslavement of mankind. Best exemplified by him talking to a subordinate about turning his failure into a "teachable moment" by making him eat himself.
The angel Metatron poses as an ally of Castiel, only reluctant to get involved because he's not a fighter by nature. At the end of Season 8, he's revealed as a scheming megalomaniac willing to sacrifice any human or angel to rule. Even after that he's always politely joshing the Winchesters and Castiel.
Azazel, the show's first Big Bad and the former King of Hell, treats Sam and Dean like old friends and frequently compliments them. In the S1 finale, while possessing John, he chides Dean for killing some of his demon brethren: "How would you feel if I killed your family? Oh right, I did. Still, two wrongs don't make a right." In the Season 2 finale, he even thanks Dean for making a Deal with the Devil to bring Sam back because he much prefers getting Sam to start the Apocalypse to his backup plan.
Hell's Queen Bitch Lilith falls firmly into this. She's a Psychopathic Manchild who loves possessing little girls and gradually forcing them to kill everyone they care about, all the while still keeping the demeanour of a sweet little girl.
Zachariah, even after the Evil All Along reveal, puts on a pretense of being a Well-Intentioned Extremist who only wants to destroy half the world because it's God's will and what remains will be a paradise. In reality, though, he's a complete slimeball who doesn't give a crap about Earth, God, or anything besides himself. When Dean tries to get him to sacrifice himself for the cause, he immediately drops the act.
During Season 6, Sam is this as a consequence of not having a soul. He still tries most of the time to act the way he thinks Sam would have, but every now and then, he lets out a clue that he's Not Himself, like deliberately allowing Dean to get bit by a vampire in "Live Free or Twihard", or in "Clap Your Hands If You Believe..." when he tells a woman at a convention that he's "had time to adjust" to his brother getting abducted by aliens.
Unnamed: Did it happen when you were kids? Sam: No. Half an hour ago.
Crowley's mother Rowena cultivates an image as a caring and motherly Family-Values Villain in order to manipulate her son and control Hell from behind the scenes. When Crowley isn't there, though, she freely admits that she doesn't love him and would gladly kill him if it were convenient.
The Thick of It: Malcolm Tucker is perfectly capable of being very polite when it suits him. It usually suits him as the setup for a string of abuse so painful you may find it psychologically impossible to move for several minutes afterward.
The Tribe: The Techno leader Ram, while not really pleasant, maintains a humorous and playful demeanor while reveling in his own wickedness. For instance, he shoots one of his officers for a minor failure in front of the rest to set an example. When Siva walks in and screams in horror, Ram instantly changes tone and joyously asks her what her day was like.
The Twilight Zone (1959): Gunter Luzte from "Deaths-Head Revisited" was a vicious Nazi commander who nevertheless acted with the joviality of a summer camp counselor toward his victims.
Russell Edgington. While more of a invokedTrue Neutral in the book series, he starts out as very Affably Evil in the series...up until his lover is killed and he progresses into insanity. Combined with his 3000 years of age, his mental instability makes him the most dangerous thing in the entire series.
Marnie Stonebrook. At first, she hid in her shell of being shy and reclusive, then turned into Affably Evil territory...before she had her Villainous Breakdown.
Ultraman Orb: Jugglus Juggler. The few times he tries to act charming or friendly, it is overshadowed by his pettiness and creepy, preening nature.
Ultraman Taiga: Kirisaki/UltramanTregear, be it in human or Ultraman form. Kirisaki keeps a jovial and friendly gesture while causing chains of catastrophic events throughout the series all with a smile on his face. The only instance(s) Tregear drops the behavior is during his confrontation with his former friend Ultraman Taro, and when the Tri-Squad bond together to form Taiga Tri-Strium and getting ass handed.
The Walking Dead (2010): Negan Smith affects a laid-back, smiling, and friendly persona even when he's enslaving people and killing their friends. He acts like he's doing people favors and demands to be thanked for the meager privileges he deigns to give.
The Cigarette Smoking Man is usually courteous when dealing with Mulder and/or Scully, speaking gently and making a show of concern over their problems. He drops the act and acts nasty toward Skinner, whom he basically considers hired help.
The episode "Signs and Wonders" revolves around two Christian ministers. Enoch O'Connor is a wild-eyed snake handler who seems to embody the most strawman version of fundamentalist Christianity. Samuel Mackey is a gentle Reasonable Authority Figure in a mainline Protestant church. Mackey actually turns out to be the Devil, or at least a high figure in Hell, and O'Connor was the only one who could perceive it.
sums it up.