In some scary movies, the sources of horror are closer than in your town or even in your house — they’re in your very own skin.

These films belong to a subgenre called body horror: movies that depict various transformations, mutations and degradations of the human form. The terrifying changes often emphasize the futility of our efforts to control our horribly unpredictable bodies. We like to think of ourselves as a mind managing a body, but these movies remind us that we’re ultimately at the mercy of the meat sacks we walk around in.

Coralie Fargeat’s newest film, “The Substance” (in theaters), starring Demi Moore and Margaret Qualley, participates in this robust tradition, depicting an aging starlet who uses an experimental new drug to create a younger, better version of herself. As you might guess, the treatment causes some unexpected and disgusting side effects, satirizing society’s (and particularly Hollywood’s) obsession with wanting women to stay stereotypically beautiful and youthful — at any cost.

If you’re looking for a primer on the subgenre, here are eight films that will give you a crash course in the gutsy, the gory and the goopy.

“The Thing” (1982): The mutations that populate this film from John Carpenter are as numerous as they are memorable. When an alien that can take the form of its victims targets a remote research outpost in Antarctica, the men stationed there try to defend themselves while becoming increasingly suspicious of one another. The beast could look like anyone before transfiguring into a horrible mockery of their visage — like when the head of one member of the team detaches from his body and grows legs like a spider. This elicits paranoia not just about one’s own body but also the bodies of others. Some viewers even see this film through the lens of anxieties surrounding the AIDS epidemic. (Stream it on Peacock.)

“The Fly’ (1986); It’s hard to pick just one film from the so-called father of body horror, David Cronenberg, to add to this list. But his remake of the 1958 monster movie “The Fly” is generally considered the most quintessential. For good reason: The practical effects used to illustrate a scientist’s slow, torturous transformation into a fly-human hybrid after a teleportation experiment runs awry won Chris Walas and Stephan Dupuis the Oscar for best makeup that year. And lines like, “You can’t penetrate beyond society’s sick, gray fear of the flesh” are the perfect introduction to the corporeal philosophizing that permeates most of Cronenberg’s work. (Rent or buy it on major platforms.)

“From Beyond” (1986): This Stuart Gordon-directed adaptation of an H.P. Lovecraft story wastes no time getting to the good stuff. In a chaotic introduction that plays like a third act, we’re quickly introduced to a machine that opens the door to a parallel world full of goopy monsters and otherworldly pleasures. One of the scientists gets pulled to the other side, and he grows increasingly, delightfully malformed. The slimy creature he becomes is lit in shades of neon pink, keeping it fun even when it gets freaky. (Stream it on Amazon Prime Video.)

“Hellraiser” (1987): I’ll let the supernatural, leather-clad, body-modified villains of Clive Barker’s shocker introduce themselves in their own words: “Demons to some, angels to others.” Like in “From Beyond,” the line between pain and pleasure is very blurry here, this time in a more religious context. Frank (Sean Chapman) awakens these demonic angels, called Cenobites, when he solves their puzzle box, unleashing mutants with pins driven into their heads and flesh pulled back with wires. They tear him apart, and he spends most of the movie skinless, accepting human sacrifices and feeding off their life force to regenerate. The leather-bar aesthetic of the Cenobites gives the body horror in this film a defiant queer edge. (Stream it on Amazon Prime Video, Hoopla and Tubi.)

“Tetsuo: The Iron Man” (1989): In Shinya Tsukamoto’s experimental, tightly packed film (the running time is 67 minutes), the mutations are mechanical. After a businessman runs over a man described as a “metal fetishist,” he himself begins to mesh with machines. Shot entirely on black-and-white, 16-millimeter film stock, with minimal dialogue and an industrial, clanging score, this movie is the most artistically bold and distinctive one on the list. Many of the transformation sequences are stop-motion, giving the movements an inorganic, stilted feel, like an engine breaking down. Get ready to get gritty, oily and sweaty. (Stream it on Arrow and Asiancrush.)

“The Human Centipede” (2009): Many of the dreaded acts that happen in this infamous torture movie directed by Tom Six are best left undescribed here. But because of the film’s widespread cultural impact, you may already know the basic conceit — three humans are captured and sewn together by an evil scientist. The concept alone was so shocking that even though few people actually saw the movie, it became the subject of whispered playground rumors, tattoos and a South Park episode. There’s something to be said about a movie so depraved in its degradation of the body that you don’t even have to watch it to be scandalized by it. (Rent or buy it on major platforms.)

“Tusk” (2014): The director Kevin Smith, famous for quirky comedies like “Clerks,” may seem an outlier here. But while Smith’s movie about a podcaster who gets surgically sewn into the shape of a walrus by a crazy mariner has its humorous moments, the result is deeply disturbing. The titular tusks, for example, are made out of the podcaster’s shaved-down tibia bones. My former housemate, a vegan, who found me watching this in our living room and sat down to join, transfixed and traumatized, has this to say six years later: “It still haunts me.” (Rent or buy it on major platforms.)

“Titane” (2021): Pregnancy is a natural subject for a subgenre concerned with uncontrollable body metamorphoses. Julia Ducournau’s second film (her first, “Raw,” is also a bloody masterpiece), combines pregnancy horror with twisted explorations of gender and the mechanical. It follows Alexia, a serial killer with a sexual proclivity for cars, as she develops an unlikely and unnatural pregnancy and disguises herself as a boy who went missing 10 years earlier. The plot points are outlandish, but the themes are subtle and psychological: the ways we contort our bodies for love. (Stream it on Hulu.)