Friday marks the 20th anniversary of Joss Whedon’s groundbreaking series “Buffy The Vampire Slayer.” This  week, I’m looking back at some of the most important elements of the show’s legacy.

It’s no mistake that “Buffy the Vampire Slayer” became a great show, and a great feminist work, as the series began to sharpen its major villains, who became known as “Big Bads.” Part of what makes Buffy Summers (Sarah Michelle Gellar) herself such an important character is her unique synthesis of power and personality, and the ways in which her frivolity and femininity coexist with her embrace of her destiny and her development as an ethical thinker and a leader. Buffy and her friends represent some of the ways women find way to wield power and to pursue fulfilling personal lives, and the villains they clash with reveal a complementary spectrum of misogyny.

The first of these great villains was Sunnydale Mayor Richard Wilkins (Harry Groener), who governed Buffy’s hometown for generations by paying homage to demons.

Wilkins’s menace bore a direct relationship to his geniality. He disdained cussing, adored his late ex-wife and presented himself as something of a family-values traditionalist, which seemed to be enough to prevent Sunnydale’s residents from looking too closely about whether their mayor was doing enough to stop vampires and demons from running rampant through town. The Master (Mark Metcalf), the powerful vampire who was the first season’s Big Bad, was a traditionalist of a baroque sort, devoted to prophecy and ritual, his evil and contempt for Buffy as obvious as the prosthetic makeup Metcalf wore to play the ancient bloodsucker. Wilkins surpassed the Master as a villain by reminding audiences that a dangerous fondness for the past or a penchant for concentrating power into the hands of a few men doesn’t always parade itself in grotesque and obvious fashion. These repressive traits can be rendered anodyne, cheery and appealing; they can be something that people are induced to choose for themselves.

Mayor Wilkins was also proof that a willingness to promote and deploy an individual woman isn’t necessarily proof that a man in power is progressive. During the third season of “Buffy the Vampire Slayer,” Mayor Wilkins groomed Faith (Eliza Dushku), a Slayer who grew up in much more difficult circumstances than Buffy and lacked Buffy’s moral code and relatively strong sense of self, as his disciple.

In keeping with his family values image, Wilkins rejected the possibility of a sexual relationship with Faith, who had long believed that was all she had to offer. But that didn’t make Wilkins any less Faith’s abuser, someone who kept her and protected her and convinced her that only he truly understood and valued her, all while continuing to shape her into a murderer. “Buffy the Vampire Slayer” pulled off a particularly deft balancing act in the mayor’s relationship with Faith: Wilkins genuinely does love Faith, and she responds to his treatment of her, but that doesn’t make the relationship any less tragic or disruptive. As with many stories on “Buffy the Vampire Slayer” over the years, especially Buffy’s relationship with the vampire Spike (James Marsters), the arc that portrays Wilkins’s relationship with Faith lives in the ambiguities and complexities of the situation instead of trying to resolve them neatly.

Three seasons later, “Buffy” began a similarly complex journey with the introduction of the Trio, a team of aspiring supervillains that consisted of Buffy’s high school classmates Jonathan Levinson (Danny Strong), Andrew Wells (Tom Lenk) and Warren Meers (Adam Busch). The Trio is one of the most farsighted creations of “Buffy The Vampire Slayer,” anticipating the subcultures like so-called Men’s Rights Activists and the Gamergate movement, which broke into the political mainstream in 2016 as part of the larger coalition of the alt-right.

The Trio represented a desperate longing for social success that gradually evolved into a toxic sense of entitlement to power and sex. “Buffy” was often sympathetic to the first element in that equation, even as the show was clear-eyed about the damage that desolation could do to others. In the third-season episode “Earshot,” delayed after the Columbine massacre, Buffy investigates what she believes to be a plan for a school shooting, only to discover that Jonathan intends to commit suicide. The next season, Jonathan reappears as a developing magician, having cast an illusion that convinced Sunnydale residents that he, not the Slayer, was responsible for protecting them — and also, in a nice bit of anticipation of the alt-right’s obsession with “The Matrix,” that Jonathan himself had starred in the movie.

That illusion is the key to the ugly road the Trio eventually walks down: Jonathan, Andrew and Warren don’t understand what it means to genuinely earn love and esteem. Warren, the most frightening of the three, is often willing to go the furthest to simply take what he thinks he is entitled to. He builds compliant sexbots for himself and for Spike, and uses a magical orb to brainwash his girlfriend Katrina (Amelinda Smith) after she breaks up with him, dressing her in a French maid costume and forcing her to serve him and his friends. When Katrina breaks free from Warren’s enchantment, telling the three that “This is not some fantasy. It’s not a game, you freaks. It’s rape,” Jonathan and Andrew react with shame, but Warren wants only to shut her up. He kills her, and then tries to frame Buffy for Katrina’s death.

It’s a formula in which Warren and his friends are entitled to everything but responsible for nothing, almost a complete inversion of Buffy’s embrace of her responsibilities and the personal difficulties that flow from them. And one of the scariest things they accomplish, though not through any plan of their own, is convincing Buffy’s best friend Willow (Alyson Hannigan) to embrace the same logic. Willow’s violent spree after Warren accidentally kills her girlfriend Tara (Amber Benson) is animated by Willow’s conviction that she has the right not merely to judge Warren, but to subjugate the entire world to the whims that sprint from her pain.

Of the villains Buffy squares off with, the Trio are among the most human: they’re young men, not vampires or demons. This means that they do evil because they choose to, not because it’s a part of their nature, a factor that makes many of their choices, particularly Warren’s attempted rape and murder of Katrina, even more repulsive. But in keeping with the series’ interest in redemption and moral evolution, Andrew ultimately finds a way to be a decent in the series’ final season by putting himself in service to Buffy’s mission. It’s not so much that Andrew accepts a lesser place in a hierarchy with the Slayer, but that he learns that hard work in service of a good cause is a sturdier route to the affection he claims. The genuine love and respect of a small circle turns out to be worth more than ersatz mass adulation. Not all angry young men who conjure are permanently lost.

And not all of the agents of the patriarchy in “Buffy the Vampire Slayer” were men. Take Maggie Walsh (Lindsay Crouse), a charismatic professor Buffy meets during her first semester of college, who turns out to be running the Initiative, a secret government program that researches demons and methods of fighting them.

Walsh is a strong woman who has succeeded in the male-dominated fields of science and the military, but that doesn’t necessarily make her a feminist. She drugged the soldiers serving under her, including Buffy’s boyfriend, Riley Finn (Marc Blucas), turning them into hyper-masculine super-soldiers, all while building an even more perfect soldier, Adam (George Hertzberg) out of machinery and demon parts. Walsh initially views Buffy as a valuable recruit, before growing disillusioned with her independent thinking and Buffy’s growing relationship with Riley, who Walsh views as a surrogate son. Walsh is a particular archetype: a strong woman who wants to keep other strong women under careful control. Walsh’s belief in her own righteous vision leads her to a terrible end: Adam kills her, but keeps her body animated with technology and magic. The system she excelled in, despite her gender, has turned on her, transforming her into a mindless zombie.

In contrast to Walsh’s brusque, butch presentation, and Buffy’s own combination of fluff and steel, the fifth-season Big Bad, Glory (Clare Cramer) represented a kind of misogynist vision of femininity run mad. Glory was a goddess from a hell dimension, incarnated most memorably as a curvy blonde with a penchant for body-conscious dresses and bright red lipstick and a tendency towards tantrums that bring down buildings. Her entitlement matches that of the Trio’s, with the difference that, being a goddess, Glory has actual worshipers she can abuse. Both she and Warren have a tendency to think of themselves as victims, and to offload responsibility onto other people.

And Glory is a hysteric, prone to ranting that “I look around at this world you’re so eager to be a part of, and all I see is six billion lunatics looking for the fastest ride out. Who’s not crazy? Look around, everyone’s drinking, smoking, shooting up, shooting each other, or just plain screwing their brains out ’cause they don’t want ’em anymore. I’m crazy? Honey, I’m the original one-eyed chicklet in the kingdom of the blind, ’cause at least I admit the world makes me nuts.” And when Glory needs a surge of power, she literally steals other characters’ reasons, draining their brains and leaving them husks.

In fact, Glory represents an idea of what it means to be a woman that could have emerged from the imagination of Caleb (Nathan Fillion), a reincarnated preacher and serial killer of young women who becomes the manifestation of the First Evil in the final season of “Buffy.”

“I’m not here to lecture you,” Caleb tells a girl he picks up late at night, while she is running from hooded pursuers. “What’s the point? The words just curdle in your ears, wouldn’t take in a thing. Head filled with so much filth there ain’t no room for words of truth…Gaping maw wants to open up and suck out a man’s marrow.”

For all that crosses and holy water are part of a vampire slayer’s arsenal, “Buffy The Vampire Slayer” never dabbles too deeply into Christian theology, until Caleb shows up preaching a warped version of Gospel. And Caleb, who shows up late in the show’s seventh season, isn’t really around for long enough to qualify as one of the best “Buffy” Big Bads. He doesn’t represent a constituency or even really stand in for a large-scale public suspicion of the Slayer: just as Buffy is a vessel for the forces that stand against the darkness, Caleb is a vessel for the First Evil, but unlike Buffy, he’s not on the show long enough to develop his own ideas about and relationship to those forces.

But he is the catalyst for the democratic idea that concludes the run of “Buffy the Vampire Slayer.” If the show was initially about an unexpected Chosen One, in the series finale, Buffy gave up sole responsibility for carrying that mantle, activating the power of every girl in the world with the potential to serve as the Slayer. Patriarchal authority on “Buffy the Vampire Slayer” wasn’t merely about limiting power to men: it tended to be about concentrating authority in a single person. Replacing a lone hero with a whole network of women was a way of rejecting both elements of that idea: the teenage girl in a man’s role gave way to a genuinely feminist vision of action storytelling.