I want to propose Madame Medusa from the 1977 film, The Rescuers.
Who Is She and What Has She Done?
Madam Medusa is a procurer of rare stones, who runs a pawn shop in New York City, which she uses as a screen to cover up her criminal activities. She uses, as her 'business partner' and dogsbody, a certain Mr. Snoops. As the story unfolds, it becomes obvious that she has been made aware of a pirates' treasure chest that houses the world's biggest diamond, the Devil's Eye and recruits Snoops, having promised him a share of the profit, to inhabit a run down riverboat in the swampy surrounds of a place named Devil's Eye (presumed to be set in Louisiana) because it is impossible for an adult to enter the blowhole to the cave, she has kidnapped a little girl from an orphanage located in the same street as her pawn shop in New York City. The child, whose name is Penny, has been missing, we learn for some time and it is presumed that she has run away with the result that the police have stopped searching for her. The mice from the Rescue Aid Society, an organization with delegates from all over the world with their headquarters in the UN building, aims to help people in distress. They convene a meeting because a bottle has been found with a message inside. It is a distress note from Penny who calls for help and mentions the orphanage's name from which she comes. The information is the starting point of the search which is undertaken by two mice, Miss Bianca from Hungary and her choice of partner, Bernard the Handyman. They visit the orphanage, spot a box with Penny's name on it and encounter an old cat named Rufus who relays the story of how Penny went missing one day. We get the impression that Penny desperately wished to be adopted and to find a happy, forever home. She had spoken of a strange woman who had tried to lure her to get into her and although Penny resisted, judging by Medusa's aggressive personality, it can be assumed that she strong-armed the child. Rufus directs them to her pawn shop and they overhear her speaking on the phone to and admonishing Snoops for having been lacks in his pursuit of the diamond. The viewer realizes that they are using the Penny to access the cave and to search around for the Devil's Eye and because up to this time, she has been unsuccessful, Medusa decides to go down to the bayou herself and force the procedure forward. It appears to be a dangerous venture and the chances of Penny getting hurt or drowning are very high. Bianca and Bernard arrive at the bayou having been transported by a quirky albatross named Orville and upon landing; they meet the interesting animal fraternity that inhabit the swamp that are well aware of Penny's plight but are unable to act. This is when the audience is introduced to Medusa's 'pet crocodiles Brutus and Nero, just as nasty as their owner and serve as guards of over Penny who tries to escape the bayou frequently. Medusa, using a manipulative, cruel kind of psychology to convince the child that nobody could possible want a plain, uninteresting child, makes the little girl feel very inadequate and worthless. Medusa implies that her fate is tied to serving her and we get the impression that once Penny has found the diamond, her use will have been expired. Medusa veers between both being kind and abusive in order to threaten the child to do her bidding. Everyone and everything cowers under her brutal personality, existing in fear of her. Penny is forced once again, to descend into the cave under the supervision of Medusa this time with Bianca and Bernard in tow to search for the Devil's Eye which Bernard spots placed in a skull. At this point, the tide is rising in the cave and staying down within its confines becomes dangerous. With much effort, the mice and Penny dislodge the diamond, barely managing to escape the whirlpool that the rising tides causes. Unfortunately, the child announces to Medusa that she has found the diamond and is coaxed to place it in the bucket in which she is lowered and hoisted back up. A tussle ensues between Medusa and her lackey Snoops for possession of the diamond and she finally admits that she'd had no intention of sharing the profit with him. Meanwhile Penny is left hovering in the bucket above the blowhole and almost falls back down into the cave. Medusa resorts to threatening, at gunpoint, Snoops and Penny in order to make a getaway. Penny's dearest possession, with which she is never without is her teddy bear, the child relies on the comfort the toy brings her. It holds a very special place in her life and Medusa, knowing this, confiscates the toy into which she has sewn the diamond. She tries to make an escape on her swamp mobile and is intercepted by the mice and the swamp community that thwart her plan. In the last scene, Penny has become a minor celebrity and has been adopted by a couple. She puts her success at busting open Medusa's crime ring to the help of two little mice much to the confusion of the world. Bianca and Bernard, much satisfied with the outcome, set their sights on a new adventure.
In my opinion, Medusa is the ultimate type of villain. The level of depravity that governs everything she does is mind-boggling. She runs the gambit of evil intention and cruel deeds. Medusa is the ultimate narcissist, completely absorbed in her own desires and is prepared to go to any length to realize her ambitions.
Medusa is a product of her own evil propensities. There is nothing to suggest that her youth or any disaster in her life drives her actions. She is covetous, greedy and vile with no care for anybody or anything but herself.
Moral Event Horizon
When Medusa kidnaps Penny, the moral event horizon is reached, and from there her deeds and thoughts become completely heinous.
It is assumed within society that a ditzy, ridiculous, over-emotional woman is incapable of true evil. She appears to be impulsive and clumsy and it is with this impression in mind that children are raised not to fear women of this type. Medusa resorts to physical violence when she grows impatient, her techniques to manipulate Penny's mind are finally honed and extremely destructive. She displays psychotic tendencies in the way she reacts and could be considered a complete sociopath. She has no respect for life and is entirely lacking in empathy.
Medusa chooses to disregard any kind of moral agency when it comes to her dealings. She is an intelligent woman, so there is no excuse from the point of view that she might be impaired in her judgement.
Kidnapped a child especially for selfish, evil reasons with the intention of eliminating that child once its use is expended, is the worst possible crime any person is able to commit against humanity.
Medusa can be considered pure evil from any perspective. There is absolutely nothing with which to redeem her. The reason in my opinion, Medusa is such a fearsome villain, is that she is entirely real. There are Medusas' in every city, town and community, often overlooked as quirky, middle-aged women.