WARNING: The following contains spoilers for American Horror Story: Double Feature Episode 3, "Thirst," which aired Wednesday on FX.

American Horror Story uses its supernatural manifestations to highlight the horrors of an all-too-human variety. Two of the show’s darkest moments have nothing to do with ghosts or demons. They’re simply reflections of human beings' casual cruelties toward each other and how utterly horrifying they can be. Both reflect appetites that cross the realm into blasphemy. As such, the series more overtly fictional ghouls are often created amid such tragically real acts.

Season 10, Episode 3, “Thirst,” takes a brief but disturbing dive into such a corner, when its protagonist is abducted by a pair of drug users making a snuff film. It echoes an equally horrifying moment back in Season 4, which shares the same bona fide credentials. They rank among American Horror Story's most unsettling moments -- a crowded field since the series has covered everything from cannibalism to nuclear holocaust -- and help keep the campier elements from sliding into poor taste.

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The first snuff film storyline appeared in Season 4, Episode 4, “Edward Mordrake, Part 2.” Elsa, the leader of Freak Show’s titular carnival, explains the circumstances under which she lost her legs. She worked as a dominatrix in the Weimar Republic before the war until she was tricked into appearing in a snuff film. The pornographers cut her legs off with a chainsaw on camera, then distributed the footage throughout Europe. A smitten customer saved her, whom she grew to despise for not letting her die and sparing her the shame of it.

Elsa’s torturers never came to justice, at least as far as American Horror Story has specified. “Thirst,” at least, carries the trappings of something more than brutality. In search of fresh blood, Harry calls upon a person offering to sell obviously stolen items on Craigslist. He’s clocked over the head and awakens tied up in the basement, where the woman and her lover are planning to record his rape and murder. They go into horrific details about the nature of his impending suffering before he uses his newly sharpened teeth to cut through his ropes and kill them both.

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Neither of the two intended victims were innocents at the time. Elsa was deeply involved in the seamier side of German society, while Harry killed and assisted in killing well before falling into the clutches of his captors. Indeed, he fully planned to murder the woman and take the blood to his daughter Alma, who had also taken the pill. That doesn’t make the crimes against them any less horrific, and in the case of “Thirst,” Harry’s victims richly deserved their bloody deaths.

However, both incidents mark a turning point for their characters, when they can justify murder far more readily and happily against figures far less deserving than their would-be torturers. It’s a moment of darkness they can’t come back from when they see how awful human beings can be left to their own devices and let some part of their better selves die in the process. But embellishing either incident with something overtly supernatural would have distanced them from their unsettling reality. Human beings did these awful things, and they enjoyed it.

As brutal as they are, such elements are a necessary part of American Horror Story’s construction. For all of its arch references and camp excess, it endeavors to genuinely frighten its audience, and it doesn’t need to stray far to do it. “Red Tide” -- the first half of the show’s Double Feature season -- draws a great deal of inspiration from Stephen King, who used stories like Salem’s Lot to suggest that supernatural forces are attracted to much more ordinary kinds of evil. The show has benefitted from taking those lessons to heart and periodically reminds its viewers that its biggest scares are disturbingly real.

New episodes of American Horror Story: Double Feature air each Wednesday at 10 p.m. ET on FX.

KEEP READING: AHS: Double Feature Episode 3, 'Thirst,' Recap & Spoilers