The popular video game The Exit 8, published, in 2023, by the Japanese indie developer Kotake Create, is what aficionados call a “walking simulator,” and what I’d call elegantly minimalist existential horror. You, the player, amble through an eerily underpopulated subway station, which gradually comes to resemble a metro-themed infinity loop—a maddeningly repetitive circle of mid-transit hell. Fear may thrive in the shadows, but here, under bright fluorescent lights, the terror feels even more malevolent, something ambient and inescapable. A yellow sign overhead points in the direction of Exit 8, but no matter how far you go, Exit 8 stubbornly refuses to appear. A man walks toward and then past you—and he will pass you again and again, the same man, in the same corridor, with only the scantest variation each time. He’s proof that you are stuck in a simulation, one that is either experiencing an unfortunate glitch or operating exactly as the devils in charge had hoped.

It’s probably a good thing that I hadn’t played the game before seeing “Exit 8,” a fiendishly clever feature-length adaptation by the director Genki Kawamura, who wrote the script with Kentaro Hirase. The movie, which runs ninety-five minutes, is sleek and precise, but, compared with the economy of the source, it’s almost a maximalist affair. At the outset, we share the perspective of someone who is identified only as the Lost Man (played by the pop star and actor Kazunari Ninomiya). As he listens to music and scrolls on his phone aboard a crowded subway train, we see what he sees and, just as crucially, hear what he hears: when an angry commuter yells at a mother to silence her crying infant, the Lost Man looks away and turns up his music. Exiting the train, he gets a call from an ex-girlfriend, who announces that she’s pregnant with his child and asks what he plans to do. He has what appears to be a panic-induced asthma attack, fumbles for his inhaler—and keeps walking.

With this narrative armature established, the game can begin. Soon, the Lost Man is navigating a telltale maze of white mosaic-tiled walls, where that Exit 8 sign looms into view; he is stranded in the underground purgatory, and so are we. At this point, the director of photography, Keisuke Imamura, ditches the rigid first-person P.O.V. in favor of a more traditional shooting style, allowing us to see the Lost Man, our avatar, moving in the frame; most of the action is composed in long takes of a flowing, sinuous elegance, which convey the sensation, by turns pleasurable, frightening, and paradoxical, of moving continuously through a contained space. It’s hard not to think of the gliding tracking shots in Stanley Kubrick’s “The Shining” (1980) as an inspiration, even before a wall of murky water comes surging at us from around the corner, like Kubrick’s tidal wave of blood.

The rules of this netherworld announce themselves, early on, via a nondescript wall sign. “Do not overlook any anomalies,” it says. “If you find an anomaly, turn back immediately.” An anomaly, the Lost Man realizes, can be a visual, aural, or situational discrepancy of any kind: a light fixture tilted at a bizarre angle, a door that swings open without warning. Every time he confirms that the corridor is anomaly-free and keeps walking—or recognizes a deviation from the usual pattern and retreats in the opposite direction—he is rewarded with a marker of progress: a sign that reads “0,” then “1,” then “2,” leading, presumably, all the way up to the elusive “8.” If he makes a mistake, his progress resets to “0” and the whole Sisyphean ordeal reboots. We scarcely need reminding that “8” is an upright infinity symbol.

The Lost Man is trapped, then, in something of a hybrid puzzle: an escape room by way of a diabolical memory test. Kawamura and the production designer Ryo Sugimoto have tweaked and expanded upon the game’s spare visual elements, updating, among other objects, the wall posters where several of the trickiest anomalies lie. One poster is now a print of M.C. Escher’s “Möbius Strip II,” which depicts nine red ants marching up and down an endless loop of metal; like the strains of Ravel’s “Boléro” that play over the film’s opening and closing moments, the image is meant to place us in a suitably circular frame of mind.

These are thematically on-the-nose gestures, but Kawamura, unlike the game’s creators, doesn’t place a premium on subtlety—or, for that matter, interactivity. As audience members, we are, of course, watching the Lost Man figure out clues and then choose whether to go forward or backward, rather than making those decisions for ourselves. For all that, there’s no loss in engagement. Kawamura and Hirase seem to have perceived the immersive limitations of the movie medium—and, rather than fighting those limitations, adapted their story accordingly. What they’ve emerged with is the rare picture that feels at once true to and ultimately subversive of its source.

It wasn’t until after I’d seen Kawamura’s movie—and idly played a few rounds of The Exit 8 on my phone—that I fully appreciated the extent and nature of that subversion. Some of it has to do with the understated grace of Ninomiya’s performance as the Lost Man, whose gentleness of spirit, even under anxiety and duress, rang a distant bell. (It took me a moment to recognize him as the actor who played Saigo, an untested, good-hearted Second World War soldier, in Clint Eastwood’s “Letters From Iwo Jima,” from 2006.) But there are other deviations as well. The Lost Man isn’t the only one who assumes control of the film’s narrative, which is divided into three chapters, each centered on a different figure. One of them is the aforementioned passerby in the corridor, known here as the Walking Man (Yamato Kochi), who, far from being just a phantom projection, winds up embarking on his own tragic adventure.

To reveal more would be unwise. Suffice to say that “Exit 8” toys with a variation on the Fregoli delusion, in which a person comes to suspect that the people around them constitute a single malign entity. (The concept of the Fregoli was vividly explored in Charlie Kaufman and Duke Johnson’s aptly titled “Anomalisa.”) Within the parameters of a game—where non-player characters essentially function as different disguises for, and manifestations of, a single narrative engine—such paranoia might not be unjustified. But in Kawamura’s telling, at least two of the N.P.C.s turn out to possess an individual consciousness. The effect is to nudge “Exit 8” closer to the physical, analog world, the one where the strangers around us are flesh-and-blood creatures with dreams, desires, stories, and sufferings of their own. These include the unnamed, dark-suited metro passengers we see at the start, many of whom stare silently ahead or down at their phones. Some of them, you imagine, might be playing a game of their own.

“Exit 8” is thus an indictment of social apathy and bystander syndrome; the film, most of which takes place in a maze of underground tunnels, warns us not to succumb to a more metaphorical kind of tunnel vision. It also argues, with unapologetic sincerity, for the special care and protection of children, and implies that those who abandon the most vulnerable among us are worthy of extreme—perhaps even eternal—punishment. It scarcely seems coincidental that the Lost Man gets lost shortly after failing to stand up for a mother and her baby, and just as he’s confronted with his own crisis of impending parenthood. Kawamura makes the point explicit late in the proceedings, with a hallucinatory outdoor sequence that briefly removes us from the train station altogether—easily the story’s most glaring structural and stylistic anomaly. Was it this scene’s earnest ode to the beauty of fatherhood or the sheer sensory relief of a breach in the claustrophobic mise en scène that pushed me over the edge into tears? Perhaps it was simply the way it underscores the film’s most poignant and perplexing contradiction. To reject any anomaly, anything mysterious or unusual, Kawamura suggests, is to succumb to a soul-crushing, self-serving conformity—and to withhold possibilities of decency, discovery, and love that make any game worth playing, life very much included. ♦