There's a thin line between what's truly mysterious and what's totally bogus. A movie that leaves you feeling unclear about what's happening isn't necessarily mysterious — it may just be inept. In other words, the problem may be it, not you.

Shane Carruth's second feature, Upstream Color, a dystopian romance in which two damaged people find their way to one another, is a little mysterious. The picture is beautifully shot by Carruth himself; its tonal palette shifts easily from crisp to soft, assessing the menace and color-wheel beauty of the natural world, as well as the somewhat beige, though not necessarily safe, comforts of the city. And it's far from inept: Carruth also edited the film himself, creating a cracked-mirror narrative that gradually pieces itself together. If the structure isn't straightforward, the basic plot and ideas aren't any harder to follow than those of, say, Leos Carax's super-wiggy end-of-cinema meditation Holy Motors.

But beware the allure of the quasi-experimental one-man show: There's a stream of pretension bubbling beneath the assured surface of Upstream Color — it's singing to us, and the words sound something like, “You probably won't get this, but try anyway.” That's what keeps the film from having any emotional effect; it respects the laws of science more than the mad, vital entropy of art.

That was also true — truer, in fact — of Carruth's 2004 debut, Primer, in which two engineers build a time-travel whatsit in a garage. Carruth produced, directed, shot, edited and scored that picture. (He filled all those roles on Upstream Color as well, and he's distributing the film, too.) Primer is clever, if self-consciously so. And for a picture made on an extremely low budget — Carruth spent $7,000 — its production values are sleek and elegant, a world apart from what other burgeoning filmmakers were doing. You wouldn't catch Carruth turning a jiggling camera on desperately uninteresting Williamsburg folk.

Upstream Color is far more ambitious, thematically and technically. Even though it's intended to be the emotionally richer movie — it's at least partly a love story, after all — Upstream Color is actually more remote. It's also fuller of well-disguised baloney. Almost midway through, a man named Jeff, played by Carruth, approaches a woman named Kris (played by Amy Seimetz, also an indie-film writer and producer) on a train in an unnamed city. There's clearly something wrong: She's huddled in a corner seat, having sealed out the world with her headphones. She wears anonymity and dislocation like a hoodie.

Jeff and Kris strike up a tentative romance, pushed forward by fractured conversations and fracturing jump cuts. There's tenderness between them, and they need it: By this point in the film, we already know — as much as we know anything for sure in Upstream Color — what has happened to Kris. When we first meet her, she's an upstanding citizen with a good job in a creative field. Then an unnamed man slips her a mysterious narcotic made from what appear to be grubs. He kidnaps and brainwashes her, turning her into an automaton and forcing her to perform abstruse menial exercises and empty her bank account.

Meanwhile, the grub-drug lives and roils inside her. (Didn't Brian Ferry once sing, “Love is the grub/I'm thinking of”?) Another mysterious figure, perhaps a scientist, a musician or both (he's played by Andrew Sensenig and referred to as “the Sampler” in the credits) comes to her rescue. Or does he? His plan for her involves an anesthetized pig, some crude surgery and a possible melding of plant, animal and human life. Thoreau's Walden figures in there, too. Afterward, Kris remembers nothing.

To be bewildered by Upstream Color is to be human; the story is obtuse by design, though the filmmaking is X-Acto precise. But it's a bloodless movie, and its ideas aren't as tricky or complex as Carruth's arch, mannered approach might suggest.

The movie's chief lament can be summed up pretty succinctly: We're disconnected from nature and disconnected from one another.

That idea is played out best in Seimetz's performance, the movie's most affecting component. Even though Kris has lost her livelihood, maybe even her reasons for existing, her eyes are only half-blank — Seimetz makes sure there are flickers of life there. In math-speak, she cancels a negative value with a positive one, the mere possibility of happiness.

But what about the X factor, that elusive variable that existed in science, math and nature long before it became a music-competition TV show? That's what Upstream Color, sensuous only in the clinical sense, lacks. When Carruth, a self-taught filmmaker and former engineer, trains his camera on some scarily bright blue flowers — or on some unnervingly pristine white ones — they practically pop off the screen, like a surprise rebuke from Mother Nature. Similarly, when Jeff and Kris, stricken suddenly by agonizing paranoia, take refuge together in an empty bathtub, their intertwined limbs become a yin-and-yang map.

Meaning is everywhere you look in Upstream Color. If only life were that simple, or that easily diagrammed.

UPSTREAM COLOR | Written and directed by Shane Carruth | Upstream Color LLC | Sundance Sunset, Monica, Playhouse

Advertising disclosure: We may receive compensation for some of the links in our stories. Thank you for supporting LA Weekly and our advertisers.