She chats with an accountant and also with a curious journalist (played by the New York magazine writer Mark Jacobson), and pays a visit to a creepy sex geek whose Web site rates the services of New York’s escorts and who styles himself the Erotic Connoisseur. (He is played by Glenn Kenny, a film critic and entertainment writer  and thus a cordial screening-room acquaintance of mine  with a combination of grandiose self-regard and theatrical self-disgust that recalls Orson Welles in his Paul Masson wine commercials.) What Chelsea reveals, as she tries to refine her marketing strategies and improve her brand, is not that everyone is a whore  equating capitalism with prostitution would be an easy, moralizing route for the film to take  but rather that everyone is hustling, trying to get a bit of leverage in a tough economic climate.

Chelsea, which might not be her real name, has a live-in boyfriend named Chris (Chris Santos), who works as a personal trainer, tending to the bodies of some of the same kinds of guys who hire Chelsea for her services. The similarities between them are established a little too pointedly, but they are nonetheless thought provoking. Both Chris and Chelsea belong to a sector of the economy that depends on the blurring of certain distinctions, between service and friendship, say, or profit and affection. Therapists, exercise instructors, nannies, manicurists, bartenders  when you think about it, they are all paid for something that can easily be mistaken for love.

“The Girlfriend Experience” traces this potential category mistake in both directions. One john, as he and Chelsea strip down, rhapsodizes about the communication between them, which of course is the basis for any successful relationship. (“Yeah, totally,” she says, slipping between the sheets.) But Chelsea, who experiences a twinge of romantic jealousy  disguised, perhaps, as professional rivalry  when she sees a once-loyal client on the town with another escort, is not immune to such feelings and finds herself drawn to a sympathetic new customer in ways that throw her off balance.

This upsets Chris, and it also puts a crack in the movie’s smooth veneer of cynical indifference. The idea that Chelsea, the girlfriend for sale, is herself succumbing to the false allure of the girlfriend experience, is an interesting one, but neither the script, by Brian Koppelman and David Levien (who also wrote “Ocean’s Thirteen”), nor Ms. Grey’s cool, tentative acting can quite sustain the level of emotional complication necessary to bring it to dramatic life. Mr. Soderbergh’s fractured chronology and chilly, observant style don’t help matters. The film, having mystified Chelsea’s poise and made much of her gift for persuasive artifice, cannot manage the complication of her vulnerability or chart the terrain of her inner life.

And this may be the point, at least in part. “The Girlfriend Experience” is about, and also traffics in, the intoxification of surfaces, and to say it objectifies Ms. Grey, who is very young (just 21) and very pretty, would be more plot summary than critique. Ms. Grey, whose career in pornography has been distinguished both by the extremity of what she is willing to do and an unusual degree of intellectual seriousness about doing it, is not so much acting here as posing a series of philosophical problems, testing the conceptual and experiential boundaries between degradation and empowerment, predator and prey, person and commodity.