Audio: Listen to this story. To hear more feature stories, download the Audm app for your iPhone.

One October night a few years back, Pam Stone was downstairs watching television with her partner, Paul Zimmerman, when it struck her that their house was unusually cold. Stone and Zimmerman live just outside Landrum, South Carolina, in an A-frame cabin; upstairs in their bedroom, French doors lead out to a raised deck. That week, autumn had finally descended on the Carolinas, killing off the mosquitoes and sending nighttime temperatures plummeting, and the previous evening the couple had opened those doors a crack to take advantage of the cool air. Now, sitting in front of the TV, Stone suddenly realized that she’d left them open and went up to close them.

Zimmerman was still downstairs when he heard her scream. He sprinted up to join her, and the two of them stood in the doorway, aghast. Their bedroom walls were crawling with insects—not dozens of them but hundreds upon hundreds. Stone knew what they were, because she’d seen a few around the house earlier that year and eventually posted a picture of one on Facebook and asked what it was. That’s a stinkbug, a chorus of people had told her—specifically, a brown marmorated stinkbug. Huh, Stone had thought at the time. Never heard of them. Now they were covering every visible surface of her bedroom.

“It was like a horror movie,” Stone recalled. She and Zimmerman fetched two brooms and started sweeping down the walls. Pre-stinkbug crisis, the couple had been unwinding after work (she is an actress, comedian, and horse trainer; he is a horticulturist), and were notably underdressed, in tank tops and boxers, for undertaking a full-scale extermination. The stinkbugs, attracted to warmth, kept thwacking into their bodies as they worked. Stone and Zimmerman didn’t dare kill them—the stink for which stinkbugs are named is released when you crush them—so they periodically threw the accumulated heaps back outside, only to realize that, every time they opened the doors to do so, more stinkbugs flew in. It took them forty-five minutes to clean the place, at which point, exhausted, they dropped into bed and switched off the lights.

Moments later, something went barrelling across the room, sounding, as stinkbugs do, like an angry and overweight wasp. The couple jumped up and turned the lights back on. Looking for the stray bug, Stone pulled a painting off the wall and turned it around; dozens of stinkbugs covered the back. She opened a drawer of the dresser: dozens more. That’s when she and Zimmerman realized that they were going to have to treat their bedroom “like a hazmat situation.” “We stripped everything,” Stone said. They took the sheets and pillowcases off the bed and emptied the upstairs bathroom. They inspected the drapes by the doors and found hundreds more stinkbugs clinging to the folds. They thwacked off as many as they could, then took the drapes down to wash them. After that, they tried several more times to go to sleep, to no avail. “Literally, the instant it was dark,” Stone said, “we’d hear four or five more come out and we would turn the lights back on because they were hitting the wall above our heads and dropping onto us, which was even more horrifying.”

In the end, it took the couple almost all night to make their bedroom habitable, but since then they have never lived entirely free of stinkbugs. The day after the infestation, one flew out of Stone’s hair dryer. A few days later, she pulled a hoodie over her head, then frantically yanked it off again upon discovering multiple stinkbugs burrowed inside. Some time after that, she tacked up a horse she’d been training, jumped on, and immediately sprang back off: stinkbugs were pouring out of every crevice of the saddle. She has flicked them off the pages of books she was reading and pulled their corpses out of her jewelry box; they have crawled across the table during dinner and, drawn to the heat of the water, edged steadily closer to her in the bathtub. As she was telling me her story, one made its way across her cutting board, while another survived a swipe from her kitten.

Pam Stone’s experience is not unique. Indeed, in the annals of brown marmorated stinkbug invasions, it isn’t even all that extreme. The species is not native to this country, but in the years since it arrived it has spread to forty-three of the forty-eight continental United States, and—in patchwork, unpredictable, time-staggered ways—has overrun homes, gardens, and farms in one location after another. Four years before Stone’s encounter, a wildlife biologist in Maryland decided to count all the brown marmorated stinkbugs he killed in his own home; he stopped the experiment after six months and twenty-six thousand two hundred and five stinkbugs. Around the same time, entomologists documented thirty thousand stinkbugs living in a shed in Virginia no bigger than an outhouse, and four thousand in a container the size of a breadbox. In West Virginia, bank employees arrived at work one day to find an exterior wall of the building covered in an estimated million stinkbugs.

What makes the brown marmorated stinkbug unique, though, is not just its tendency to congregate in extremely large numbers but the fact that it boasts a peculiar and unwelcome kind of versatility. Very few household pests destroy crops; fleas and bedbugs are nightmarish, but not if you’re a field of corn. Conversely, very few agricultural pests pose a problem indoors; you’ll seldom hear of people confronting a swarm of boll weevils in their bedroom. But the brown marmorated stinkbug has made a name for itself by simultaneously threatening millions of acres of American farmland and grossing out the occupants of millions of American homes. The saga of how it got here, what it’s doing here, and what we’re doing about it is part dystopic and part tragicomic, part qualified success story and part cautionary tale. If you have never met its main character, I assure you: you will soon.

Of the five-thousand-odd species of stinkbug in the world, the brown marmorated kind is the most destructive, the most annoying, and possibly the ugliest. It is roughly the size of a dime, although thicker, but its head is unusually small, even for an insect, which gives it an appropriately thuggish look. Its six legs prop its shield-shaped body up in the air, as if they were pallbearers at the funeral of a Knight Templar. Its antennae are striped with bands of dark and light, while its eyes, should you get close enough to gaze into them, are the vivid red of an alarm clock at night. The “marmorated” in its name means “marbled,” but “mottled” is closer to the truth. Entomologists, who have a color palette as elaborate as Benjamin Moore’s, describe the underside of its body as “distinctly pale luteous” and the topside as “generally brownish cinereous, but also greyish ochraceous, ochraceous, testaceous, or castaneous.” To everyone else, it looks as dull brown as its own frass, the technical term for insect excrement.