“This is gonna be a real project, man,” a scraggly Bay Area filmmaker anxiously says into his camera at the start of “Ever Since the World Ended,” which begins a week-long run tonight at the Pioneer Theater. Like countless homegrown documentarians before him, this man has decided to make a photographic record of his community, with himself at the center.

But the film that follows is not “real.” During the course of a few first-person reminiscences by the filmmaker (played by the actual film’s co-director, Calum Grant) and a series of disturbingly offhand talking head interviews, we discover that some 12 years ago, a Central African virus swept the globe, killed untold billions of people, and effectively ended civilization as we know it.

Ingeniously written and photographed (Mr. Grant’s co-helmer, Joshua Atesh Litle, shot the film and plays the fictional documentary’s cinematographer), and performed with pitch perfect you-are-there restraint by San Francisco theater vets, “Ever Since the World Ended” is a remarkably three-dimensional, speculative chronicle of what life might be like if the world’s population was reduced by about 90%.

The film is boldly small in scale and blissfully free of the huddling burlap-wrapped victims and leather-clad ravaging gangs that are staples of most “year zero” postapocalyptic science-fiction dramas. Made on digital video and a shoestring budget, “Ever Since the World Ended” is a reminder that pragmatic, logical, and honest examination of human behavior fuels storytelling “vision” just as well as extravagant production values and bold pictorial strokes. Arguably better.

Small, self-contained collective communities have become the order of the day in the film’s parallel present. Not because communal life represents a courageous utopian experiment, but simply because there aren’t enough people left to support anything more ambitious. It’s like someone found the industrial age’s reset button and pushed it. The defunct social order is little more than a decade in the rearview mirror and humanity, such as it is, finds itself poised between scavenging from the old world and committing to creating a new one.

With the past gone and the present a process of simultaneously digging out and moving on, one of the most curiously moving casualties of the fall of Western and every other kind of 21st century civilization depicted in the film, is cynicism itself. The people of “Ever Since the World Ended,” are all on a first name basis with one another because there are so few branches left on any family tree. They remain engagingly straightforward and unpretentious, because, the movie suggests, self-deception is a luxury that only exists in a world crowded enough to distract its citizens from daily survival.

In the classic “Twilight Zone” episode “Time Enough at Last,” a bookish bank clerk played by Burgess Meredith gets his wish to read alone in peace granted when he accidentally rides out World War III in a bank vault. Similarly, in “Ever Since the World Ended,” which in its unsentimental tough-love humanism bears more than a passing resemblance to Rod Serling’s equally harsh yet homey futures, you get the impression that the end of the world was just what some of the survivors were waiting for.

The apoc-u-mock-u-mentary camera finds an unbalanced conspiracy theorist who excitedly talks up a proposed museum of the plague and the combined NSA, CIA, and CDC conspiracy he is sure spawned it. A bartering black marketer makes a sincere pitch in defense of his decidedly un-communal approach to hunting, gathering, and hoarding. The last known Native American in the Pacific Northwest recommits himself to the native crafts and traditions that now he alone knows.

But the downside of the postapocalyptic simple life is just as persuasively posed. The would-be archivist’s ambitious shrine to his own paranoia has no completion date, because there’s almost no one left to visit it. The Native American is forced to shoo away spiritually traumatized survivors arriving on his doorstep who beg for divine guidance and dream interpretation. “Of course you’re gonna have nightmares,” he tells them. “You don’t need me to tell you what that’s about. Go ask your child, they’ll tell you.”

The fate of the world’s children, and the yawning nostalgia gap separating them from their elders, is another one of this very smart movie’s many conceptual coups. Despite dogged efforts to educate the next generation in the best of the civilization that lies dead at their feet, the teens and 20-somethings of “Ever Since the World Ended” can barely be bothered to look back.

History has finally been written by the losers. Who wants to come of age expected to mourn something they never knew? Asked how she feels about the decaying bodies that are the inevitable part of nearly any daily wander, one teenager sums up her generation’s disinterest in what has come before by smiling, shrugging, and saying in a mall drawl, “they’re, like, everywhere.”

As much as one ultimately star-crossed character wants us (and the fictional documentary crew) to believe that human society’s destructive impulses have been curtailed by the death of the “fear-based media,” aggression has endured just as much as hope. In one particularly disturbing scene, a group summit argues the fate of a mentally unbalanced survivor whose behavior threatens their fragile society with a chillingly elliptical awkwardness instantly recognizable to anyone who’s ever attended a co-op board or tenant’s meeting.

Messrs. Grant and Litle’s cast deserve praise for bringing to life characters that appear to speak and feel in the actual “documentary” moments that the filmmakers have so intelligently and thoroughly contrived. Digital video is notoriously unforgiving to actors, yet in “Ever Since the World Ended,” the format’s lie-detecting quality gives the film’s well-worn brave new world premise a fresh honesty that is heartbreaking, spellbinding, and frighteningly real.