Last month, “Euphoria,” HBO’s druggy, sexy teenage soap, took a trip to the carnival. One high school student had sex in the shadow of the Ferris wheel, another brought herself to orgasm with a carousel horse. Some middle schoolers smoked weed behind the Gravitron . A prepubescent boy with face tattoos sold molly from a pretzel stand.

The sinister carnival is a staple of American popular culture. It arrives in a town, often in the summer , trailing tinsel and the aroma of deep-fryer fat, promising rebellion and reversal, a breather from ordinary life. The rides mess with physics. The noise, lights and corn dogs mess with everything else.

“It doesn’t get more American than this,” says Murray, the private eye on “Stranger Things,” in a fun fair episode that also premiered this summer. “Fatty foods, ugly decadence, rigged games.”

In midcentury works , often tasked with reinforcing social norms, the carnival itself is dangerous. Think of the death via carousel in “Strangers on a Train,” the pleasure island that distracts Pinocchio from his true path. Step right up for degradation, as in the film noir “Nightmare Alley,” or disfigurement, as in the Tod Browning shocker “Freaks.” In “Something Wicked This Way Comes,” the Ray Bradbury novel that terrified me as a kid, a carnival is a locus of pure evil.