Paz Encina’s “Paraguayan Hammock” belongs to a class of overachievers, a resplendent suite of seven films commissioned for the 2006 New Crowned Hope festival in Vienna, held in celebration of Mozart’s 250th birthday. Some are extraordinary (“Syndromes and a Century,” “I Don’t Want to Sleep Alone”), none are less than very good, and, perhaps most amazing, only one has failed to materialize on American screens. Tonight, Ms. Encina’s technically striking 78-minute debut, the last of the group, opens at Anthology Film Archives, and it does not disappoint.

“Paraguayan Hammock” is set during the country’s 1930s Chaco War with Bolivia, but our view is of anguish and absence, not action. Instead of the bloody border struggle that claimed more than 100,000 lives, Ms. Encina trains her camera on a middle-aged couple (played by Georgina Genes and Ramon del Rio) whose son is away at the front. Even this central piece of orientation emerges gradually — at first, we just see them setting up camp (or at least hammock) in a leaf-strewn forest to no clear purpose.

The study in tension and separation that follows, hitched to the passage of day into night, takes some getting used to. Long scenes of circular chatter and silence, shot at a distance, keep the two peasants’ faces just beyond intelligibility. Later sequences in a village, and in cane fields, are imbued with a late-autumnal weariness. Little develops as we are absorbed into the worried stillness, broken by the faint barks of a dog that become a point of conversation.

Maybe the most mesmerizing effect is the abstracted yet intimate sound design of the couple’s conversations. Closely miked and slightly delayed, they sound like internal monologues, and sharp eyes will notice early on that the performers do not even appear to be talking (indeed, other actors were dubbed). It’s as if their loving concerns about their son’s return lie so close to heart that they hardly even need to be voiced: They’re thinking about it all the time, turned inward even during their daily routines.

As the couple wagers on the likelihood of rain and carps about the dog (first that it’s barking, then that it’s not), we watch two people who know each other’s words before they’re spoken. Ms. Encina further links them through closely paralleled scenes as they come to long-denied realizations about their son.

As dusk arrives, with us in attendance, nothing comes to mind so much as Albert Serra’s “Honor of Knights,” which screened at Anthology last September. While Mr. Serra’s Don Quixote adaptation might seem to have little to do with Ms. Encina’s sober movie, both offer unorthodox styles that reflect a common artistic urge to innovate. Much as “Honor of Knights” successfully re-imagined a 400-year-old classic, “Hammock” answers a double challenge of national identity: It gives voice to the fraught, oft-buried events preceding the dictator Alfredo Stroessner, and is the first feature film out of Paraguay in nearly three decades.

Indeed, Ms. Encina occasionally arrays her actors in tableaus (in profile by a house, for instance, or spread about a forest) that bestow the dignity of a historical painting. These don’t disrupt the sense of exhausted anticipation, but they’re present right alongside scenes set by a tatakua, the traditional open-air oven used in Paraguay. (Also, the dialogue spoken in the film is not in Spanish, but the indigenous language Guarani.)

At its outset, “Paraguayan Hammock” may frustrate. The initial, rigidly held remove is a bit affected without the history to lend some bearings. But the modest running time signals that Ms. Encina isn’t interested in austere endurance-test cinema, and she closes her film faithfully in regard to her pained characters, lonely and fearful as night falls.

Through May 20 (32 Second Ave. at 2nd Street, 212-505-5181).