As The New Yorker’s Emily Nussbaum recently identified, the uncanny has come to feature in a surprisingly broad range of contemporary television shows. On Fox’s Wayward Pines, which debuted in May, a Secret Service agent finds himself trapped inside a small Idaho town where time skews unstably, and where the inhabitants appear to be only acting normal. In the BBC’s Orphan Black, a young woman literally doubles and triples as a clone, then assumes the identity of one of her doppelgängers. In FX’s American Horror Story, lampshades are made of human skin, and a freak show circus (what could be more unsettling than clowns?) distorts joy into grotesque horror.

The trend can also be seen in streaming shows: The dead reappear in The Returned, upending the proper course of nature; and a deceased lover is replaced with a mechanical simulacrum in an episode of Black Mirror. Even procedural dramas are suffused with weirdness: In The Fall, a mannequin is used to evoke the ghostly shape of the killer Paul Spector’s victims. Tugging out a common thread, Nussbaum labeled these shows as living and dying “by their devotion to that old Freudian concept of ‘the uncanny.’”

Sigmund Freud wrote his essay on the subject in 1919, and the intervening century has done little to diminish its fascination. The uncanny “undoubtably belongs to all that is terrible,” Freud writes, but it is categorically unique “within the boundaries of what is ‘fearful.’” Freud invokes the ambiguous German word heimlich to describe exactly what sets the uncanny apart: “On the one hand, it means that which is familiar and congenial, and on the other, that which is concealed and kept out of sight.” He offers a dizzying array of examples: wax-work figures, artificial dolls, and automatons; doubles “in every shape and degree,” including faces, crimes, or oddly recurring names. “When one wanders about in a dark, strange room, looking for the door or the electric switch, and collides for the hundredth time with the same piece of furniture”—that is uncanny. When somebody seems to possess inexplicable powers, or something is freighted with an excess of symbolic weight, like “a hand cut off at the wrist”—also uncanny. “To many people the idea of being buried alive while appearing to be dead is the most uncanny thing of all,” he concludes.

In a visual medium like television, the uncanny can work in several different ways. It can be channeled through ambient mood—the desaturated Louisiana seen in season one of True Detective, where Rust Cohle describes one location as “like somebody's memory of the town, and the memory’s fading.” It can also come in violent riffs that tear the surrounding fabric of normalcy. The uncanny is that moment in Mad Men when the camera lingers too long on a banal office party, until a secretary, riding a lawnmower around the desks, mangles a man’s foot, showering her colleagues with blood. (That there can be humor in the uncanny is a fact that many British television comedians have made their forte, from Matthew Holness to The League of Gentlemen.)