Though entirely barren of religious sanctimony, “Maria Full of Grace” deigns the prayer from which its title derives, designating it as one whispered from the present day underworld of international heroin smuggling. Written and directed by newcomer Joshua Marston, the film traces the dramatic experience of Maria (brilliantly embodied by Catalina Sandino Moreno), a young woman living in Colombia, as she slips into the role of a drug-trafficking “mule.”

The life the film portrays is as ordinary as its protagonist’s name: 17-year-old Maria has a best friend who makes for an unreliable sidekick, a sister and mother who make for undesirable role models and a boyfriend who makes for an unwanted father once Maria affirms she is pregnant by him. Her job has her de-thorning roses as an assembly line worker in a flower factory, and, once her pregnancy-induced nausea gets her fired, it seems timely for Maria to come up with a new plan – however thorny it may be.

It is with perfect timing that Maria’s guide into the drug world then appears in the form of Franklin (Jhon Alex Toro), informing her of a way in which she could earn lots of money in little time — and travel to New York to boot. This proposal holds a perverse prospect of escape for a small-town girl, as well as lucrative adventure nonetheless – especially for someone whose brazen nature transcends her circumscribed life. With the help of Franklin’s persuasion, Maria is plucked out of her home and dispatched, that is, of course, only after swallowing down as many of what look like giant marshmallows as her stomach can accommodate. After the unpalatable process of gulping them one by one, Maria takes off to America with a total of 62 plastic-wrapped pellets cushioned in her delicate frame.

What makes the film extraordinary, then, is not the life it portrays, but the stillness and patience — truly, the grace — with which it is captured. The inclusion of atmospheric subtleties enhances the authenticity of the story and its shifting settings. A brief scene in which Maria buys a tortilla from an anonymous street vendor in New York is juxtaposed with an earlier moment when, shrouded by sunlight and music, she had enjoyed a fresher and more familiar one in Bogota. In the comparison of such parallel instances, Maria’s perilous journey and accompanying sacrifice become vividly poignant. Wrapped in the chaotic complications as she begins to confront situations that are running far from perfectly, her newfound reality proves to have lost any sense of simplicity or nourishment.

It this attention to the miniscule that assures us of Marston’s integrity behind the camera through his narration of a very real aspect of the drug industry’s back story in Latin America. What makes Marston masterful is the fact that the film’s tragic elements are not announced with melodramatic grandeur; his foremost concern is to penetrate us with the quietude of the story’s humanity. He portrays the clinical process by which the drugs are prepared, packaged and by whom these things are done, as well as how they are excreted, re-swallowed — and, again, by whom.

This aura of unflinching silence pierces even the choice Maria makes in the film’s final twist.

The human level in which drug trafficking takes place is, after all, as detectable as a grape-sized pellet nestled between walls of flesh. But it is also as dire. If one pellet breaks, one human dies. It is the utter humanity at the heart of this tragic drug cycle that “Maria Full of Grace” dares us to swallow.

“Maria Full of Grace” is playing tonight at Campbell Hall at 7:30. Tickets are $5 for students.