“The Circle” is a swankly sinister little mind teaser of a thriller. It’s a nightmare vision of what digital culture is turning all of us into, with all of our help. The movie, adapted from Dave Eggers’ 2013 novel and directed by James Ponsoldt (“The End of the Tour”), is about a corporation called The Circle that stores massive amounts of data — financial, medical, social, personal — about each of the account holders who belong to it. The company, based in the Bay Area, knows everything there is to know about you — but it’s all for your own convenience! You could call “The Circle” a dystopian thriller, yet it’s not the usual boilerplate sci-fi about grimly abstract oppressors lording it over everyone else. The movie is smarter and creepier than that; it’s a cautionary tale for the age of social-media witch hunts and compulsive oversharing. The fascist digital future the movie imagines is darkly intriguing to contemplate, because one’s main thought about it is how much of that future is already here.

Mae Holland (Emma Watson) is an eager, lively, somewhat unsure-of-herself office drone who is lucky enough, through her friend Annie (Karen Gillan), to snag an entry-level job as a “customer experience” manager on the campus of The Circle. It’s one of those super-energized youth-cult work environments — think Amazon meets Apple meets Facebook — where selling what the company stands for is built into every interaction. Early on, Mae attends her first Dream Friday, the weekly corporate pep rally in which Eamon Bailey (Tom Hanks), the company’s co-founder and guru, gets up on stage to point out how everything that’s good for The Circle is good for the world. Hanks, warm and youthful in dark hair and a gray beard, plays Bailey with a disarmingly friendly, Steve Jobs–meets–Tony Robbins happy-talk authoritarian boosterism.

On Mae’s first Dream Friday, Bailey introduces a shiny round synthetic camera, scarcely bigger than a marble, that can be attached to any surface. A live feed of that environment will then come right onto your computer screen. It’s very NSA — which is to say, nothing we haven’t already contemplated in the age of high surveillance.

But then Mae, after several days on the job, gets visited at her desk by a couple of co-workers, and that’s when the real creepiness starts to play with her head. They tell her that she has already fallen behind on her social media, that she’s not sharing enough with the “community.” She is, they say, the most “mysterious” person at the company (because she’s failed to reveal every last thing about herself). They know that her father (played, in his final role, by the late Bill Paxton) has MS, but didn’t she know that the company offers a support group for children of MS sufferers? They also point out that Mae didn’t come into work over the weekend (but, they hasten to add, that’s okay, it’s not required, though it didn’t go unnoticed), and that she would do well to keep up on her unanswered community work messages, which now number 8,000. It’s all for her own good, of course. It’s so that she can connect.

In nearly every corporate thriller, the ominous bosses are the bad guys, and the workers, with one or two back-stabbing exceptions, are the victims of their malfeasance. “The Circle” presents an altogether different — and more insightful — anatomy of corporate power. Everything The Circle does fulfills a “progressive” agenda. And the bad guys are now us: the proletarian communicators.

At a work party, Mae learns that the company has devised a system to protect children from predators by implanting chips in their bones. When she laughs, in disbelief, that this could be happening, the coworker who tells her about it mentions that it’s “reducing kidnapping, rape, and murder by 99 percent.” (If you object to the idea of implanting chips in children, then it puts you on the side of defending those things.) A politician running for Congress gives a speech to the Circle members, pledging total transparency: She will make every last one of her phone calls and e-mails available. It’s the “liberal” vision of political honesty.

But, of course, what all this is doing is eliminating privacy — and, more than that, downgrading privacy to an archaic concept. “The Circle” is Dave Eggers’ variation on “Nineteen Eighty-Four,” in which Big Brother has become the compulsion of ordinary citizens to make public — and relinquish control over — their space, their lives, their selves. How far does the film go into the new consciousness? Far enough to make the principal culprit…the heroine.

Mae is recruited by Bailey and his partner (Patton Oswalt, as the compleat weasel) to become a company advocate, and before long she has embraced the cult of “transparency,” volunteering to wear a micro-camera 24/7 and turn her life into a YouTube-style reality series: “Big Brother” meets “The Truman Show.” (Ponsoldt and Eggers, who co-wrote the script, provide a witty jaded array of pop-up troll comments in on-line bubbles.) Emma Watson makes this convincing, because she gives Mae a desire to be liked that turns her cheerleading for the new technocratic agenda into something uniquely validating. She wins followers, the love of her coworkers, the approval of her bosses — and through it all she fills the hole in her soul with a new way of “connecting.” The company, in turn, gets a new way to control everyone under the sun.

“The Circle” has an elegant and original look, all sleek techno business clutter, and given its star wattage, it’s a good enough movie to find a niche in the marketplace. Watson, who’s at the center of nearly every scene, is a serious actress who proves that she can hold a film together with the force of her personality.

Yet a movie where the heroine, in her ambiguous innocence, goes over to the dark side of corporate power is not necessarily a movie you can warm up to. “The Circle” is a fascinating but chilly parable, a film for the head rather than the heart (or any place lower). It’s a bit of a thesis drama; its driving passion it to warn us about how a surveillance society will work. Mae gets up on stage to demonstrate that anyone on earth can be located in 20 minutes. She starts with a wanted killer (it’s queasy to see even that person readily apprehended), then moves on to her non-techie best friend (Ellar Coltrane, the star of “Boyhood”), whose pursuit by cell-phone camera and highway mini-drone plays like a scene out of “Invasion of the Body Snatchers.” “The Circle” is so clinical in its paranoia that it doesn’t hit many emotional buttons, but it’s the rare conversation-piece thriller that asks its audience: What sort of society do you really want? The movie shows us what it looks like when people have been convinced to share so much of themselves that they no longer have any selves left.