The Manhattan Theatre Club revival of Tracy Letts’s funny, ultimately heartbreaking psychological thriller “Bug” opens with Carrie Coon—who plays Agnes White, a lonely waitress holed up in an Oklahoma motel room—standing in front of a half-open door and holding a wineglass upside down, radiating isolation. Soon, someone picks up her signal: Peter Evans, a sad-sack drifter who has tagged along with Agnes’s honky-tonk buddy R.C. and then sticks around. Peter is a weird guy and a bit younger than Agnes, but he’s polite and willing to keep her company, to drink her wine and smoke some crack. (He won’t snort powder cocaine, though: that stuff is bad for you, he explains.) And then he wakes up with a bug bite. When Agnes can’t see a bug that he points at, frantically, he urges her to look closer. She does—and maybe she sees something.

Agnes learns that Peter, a veteran of the Gulf War, understands certain dark realities about the world—and suddenly these two strangers have everything in common. As she soaks up Peter’s paranoia about infestation and he swats away her skepticism, their conversation lights up, at once broadening and narrowing as they obsess about “plant aphids” and “coke bugs,” egg sacs and military implants. It’s a crisis that they can face together without ever leaving the room, which begins to feel like the only real place on earth. In the director David Cromer’s spare, intelligent production, the set hovers inside an inky blackness. Together, the pair build a cracked but genuine intimacy, a bond that escalates frighteningly in the second act, in a way that brought to mind the country song “Fade Into You,” which ends with the lines “There’ll be no trace that one was once two / After I fade into you.” By the show’s unnerving final moments, Agnes and Peter don’t even have to speak to know what to do next.

When “Bug” premièred, in 1996, the role of Peter was designed as a showcase for the handsome, cadaverous charisma of Michael Shannon, whom Letts met when Shannon was a sixteen-year-old launching himself into Chicago’s experimental-theatre scene. Shannon had played a trailer-trash fuckup in Letts’s early hit, the nihilist neo-noir “Killer Joe,” and for “Bug,” a more humane but equally dark-humored project, he channelled a different kind of intensity, a neuro-atypical, weirdo strength, all striated muscles and bug eyes. It made sense that Agnes couldn’t look away.

Namir Smallwood, an ensemble member at Steppenwolf, the Chicago repertory company where the new production originated, plays Peter as a much softer, more recessive figure. He’s a little sluggish, his volume turned way down. In early scenes, he exudes a puppyish, confused sweetness, and there is logic to this interpretation. His Peter is unthreatening enough for it to make sense that Agnes, who is hiding from her ex-con husband, lets him get so close to her—even after they sleep together, he seems less like a lover than like a lost child. There’s no frisson when they are naked together, as they are for long periods. He’s muted compared with the other, more intense figures in Agnes’s life: the vivacious broad R.C. (played with rangy, liberating hilarity by Jennifer Engstrom) and that mean ex. Over time, his sweetness darkens, then hollows out. When, at a key moment, Coon leaps into Smallwood’s arms in abandon, it feels like watching a person jump happily into an empty pool.

In Cromer’s framing, that hollowness begins to feel like the play’s sad theme: when someone is on a desperate hunt for meaning, the source of it ultimately doesn’t matter very much. It also turns the play into a story about Agnes, not Peter—her decision to believe, in “X-Files” terms. Coon, who is Letts’s wife, builds an Agnes who, despite her fragility and naïveté, also comes across as a sharp, observant woman—and the actress, with her pretty moon face and coltish legs sticking out of denim short shorts, has a natural likability, scoring laughs from a hundred tiny gestures, such as a skeptical glance in the mirror. Smallwood’s Peter gets a few deadpan comebacks, but by Act II he is less a seducer than a reply guy, a dedicated pattern finder pivoting to fend off challenges to his theories.

In a crucial scene, Agnes herself wonders out loud about this imbalance. “I don’t know why I love you so much. I don’t even know you very well,” she tells Peter plaintively, as they lie in bed. “I guess I’d rather talk with you about bugs than talk about nothin’ with nobody.” The reason for this is awful: everything else she could talk about is so much worse.

Maybe the strangest thing about this revival is how ordinary these characters are likely to seem to an audience in 2026, especially Peter, a figure you might stumble on in any Reddit thread. For the original production—which was staged at the Gate, the tiny experimental theatre in London—the script was written quickly by Letts as a nimble follow-up to “Killer Joe” and constructed to match the needs of an intimate space. The play has become a staple of small companies, with its one set (used brilliantly here, in ways not worth spoiling) and its series of febrile monologues, including a final one that Coon eats for breakfast. But, when “Bug” was written, it had a specific historical referent: Letts, who grew up in Oklahoma, was so shocked by Timothy McVeigh’s bombing of the Alfred P. Murrah Federal Building that he looked for answers on the then rudimentary web, where he found conspiratorial rabbit holes, freshly dug. He studied psychosis and folie-à-deux madness, investigating how mental contagions spread.

Thirty years ago, Peter’s state of mind was likely bracing and exotic for audiences. Now, in the age of covid, QAnon, Pizzagate, and the Epstein files, it’s the substance we are all soaking in, our toxic Palmolive. Although it’s never remarked on in the text, casting Smallwood, a Black man, as the only actor of color in a drama set in Oklahoma works as an intensifier for Peter’s view of the world. When he talks about the Tuskegee experiment and the Jonestown massacre, these references carry extra weight—though it also seems unlikely that he wouldn’t bring up race and that his enemies, particularly Agnes’s crude ex, wouldn’t either.

There are moments in “Bug” that seem eerily modern, including an encounter in which Peter insists that a human being is a robot. It mirrored the plot of the gonzo film “Bugonia,” in which a pair of wack jobs kidnap a C.E.O. they believe is an alien, and of the nutso ending of “Eddington”—I could go on. Contemporary culture is a delirium of both conspiracy-mongering and conspiracy-puncturing, in every medium. On television shows from “Severance” to “Stranger Things,” the people who believe the worst are inevitably correct, either because in a serialized thriller it makes sense for each sinister revelation to climb higher up the ladder—or because sometimes the head is where the fish is rotting from. The superfan mind-set can feel uneasily adjacent to a QAnon fixation.

But mystery is just as interesting. That was the subject of HBO’s “The Leftovers,” in which Coon gave one of her best performances to date, as a woman who had lost her entire family to an inexplicable extinction event, forcing her to build a new self from scratch. Her Agnes is up to something similar, this time as a team sport. At the heart of “Bug” is a romantic craving—to be with someone and not be judged for your craziest thoughts. It’s a play about painkillers of all kinds, but also about how much easier grief is to handle when it’s reimagined as a battle to be won. Terrible things may be happening to you and your partner, but you’re at the center of it, together.

Even in an era in which paranoia has become the default setting, “Bug” feels more pungent, more punishing, and—for all its perversity—more crushing than similar stories, precisely because it’s about how people “catch feelings,” not just ideas. In Coon’s openhearted, subtly joyful portrayal, Agnes is not a broken person who is tricked into faith; she is someone who makes a series of choices to get something she needs, a glue to fix a broken world. In her final monologue, this all becomes clear: it’s liberating to see a pattern in your pain, instead of a nightmare that makes no sense. Who among us wouldn’t bite at the chance? ♦