Cold Souls

Giamatti plays an actor named Paul Giamatti. He is depressed. He’s starring in a New York stage production of “Uncle Vanya,’’ and Vanya’s psychic and physical aches are Paul’s pains, too. One evening, he sees a New Yorker profile about one Dr. Flintstein (David Strathairn), who extracts people’s souls in exchange, if they choose, for someone else’s. In his misery, Paul undergoes the procedure, which requires lying down on a bed that feeds you into a big machine that looks like a Claes Oldenburg breath mint. It spits out an object that can fit into a canister (Paul’s looks like a kernel of corn). His results are initially subtle, unless you’re his wife (Emily Watson), in which case his behavior (chomping on celery while a friend grieves her dying mother) is an amusing annoyance.

Soon Paul’s ineffective, self-pitying Vanya becomes a kind of go-getter and, as far as the costar playing Yelena is concerned, a go-grabber. This new Vanya is robustly randy. He’s self-confident. So the concern that Giamatti’s self-mockery might be premature is misplaced. What we have here is a film about performance enhancers. Apparently, a soulless Paul Giamatti is a more virile one.

From this existential saga, Barthes could have made an entire film, one that puts its star through all sorts of mood variations. In doing so, I imagine she would also draw even more comparisons than she already has to the work of the screenwriter Charlie Kaufman, whose movies, among them “Being John Malkovich,’’ “Eternal Sunshine of the Spotless Mind,’’ and “Synecdoche, New York,’’ tend to fold into and comment on themselves. They feel both boundless and confined to the space of their maker’s head. This can be exhilarating, but in an exacting, intellectual way. Emotionally, they’re wrenched and stressed out, as opposed to feeling. And this is where Barthes and Kaufman part company.

As it happens, the most inspired portions of “Cold Souls’’ involve a sleek Russian named Nina (Dina Korzun) who travels between St. Petersburg and Dr. Flintstein’s high-tech office, which appears to be on low-tech Roosevelt Island. We watch this woman remove wigs and prosthetic fingerprints. We see her solicit the sick, the unhappy, and the tragic, handing one misfortunate ballerina her business card. In drug parlance, Nina is a mule, carrying the souls of people that the company she works for then sells to Dr. Flintstein in New York.

A Russian black market for souls is priceless. It is not, however, a comic end unto itself. Barthes has devised a meeting for the two halves of her movie that feels as natural as the soul extractions are unnatural. After weeks of soullessness, and having decided to rise to the challenge of doing night after night of Chekhov, Paul elects to have a new soul implanted. His replacement is that of a Russian poet - at least that’s what the Russians are saying they’re selling Dr. Flintstein. What Paul discovers and what Dina already knows is something altogether unhappier. It’s not Chekhov’s soul - but rather a soul out of Chekhov.

Barthes supplies some cheap jokes, most of them about New Jersey, that seem beneath a philosophical comedy that also wanders into the surrealist territory of Jorge Luis Borges and Milan Kundera. But you’re inclined to stay with “Cold Souls’’ because the movie’s good ideas multiply. The comedic prospects for Giamatti being the subject of a soul-swapping procedure were never in doubt. And the movie has several wonderful scenes with Katheryn Winnick as a Russian starlet desperate for the soul of Al Pacino. Still, I did wonder whether Barthes put calls in to Zac Efron or Megan Fox.

Casting someone besides Giamatti would have meant never experiencing the many roiling dimensions of his Vanya. He makes you wonder why more actors don’t go for Vanya the volcano. Korzun, meanwhile, having played similar Russians in movies like “40 Shades of Blue,’’ has mastered the fine line between automaton and spiritual ache. Both actors go a long way to getting at Barthes’s primary wonder.

What would happen if we treated our souls like an old sofa that you don’t want to get rid of, but is too heavy or too ugly to move? What if we could just swap for a nicer one. For starters, Salvation Army stores would become a lot more interesting.

Wesley Morris can be reached at wmorris@globe.com. For more on movies, go to www.boston.com/movienation.