Imagine a freshly painted in a narrow rainbow of melancholy hues. The night sky is a blue-black gunmetal. Even the sunlight that dapples the world’s filthy old back alleys and floods its antiseptic freshly-built interiors appears to have been painted on. Now imagine watching that paint gradually dry for 2 1/2 hours and feeling sorry when it ultimately ends.

It would be too easy to describe Portuguese filmmaker Pedro Costa’s latest film, “Colossal Youth,” opening today for its American premiere at Anthology Film Archives (kicking off a retrospective of the director’s work) as a challenging film-going experience. An episodic and, for the most part, rigorously static compendium of dramatic monologues and conversations between the uprooted residents of Fontainhas, a Lisbon ghetto since demolished by urban renewal, Mr. Costa’s film is repetitive, formal, and austere to a fault.

But “Colossal Youth” is only an ordeal if one recoils at the prospect of joining in a rondo of authentic and intimate autobiographical confessions that are as deeply and subtly troubling as they are easy for Mr. Costa’s cast of non-actors to present.

While filming 1997’s “Bones” and 2000’s “In Vanda’s Room,” Mr. Costa befriended Ventura, a solemn and aging Cape Verdean native at the end of his career as a construction laborer in Fontainhas. At the time, the neighborhood and its maze of dilapidated old buildings and shacks was being razed and its residents were relocating to new government housing.

While making his two previous films in Fontainhas, Mr. Costa had grown enamored of the people he’d met and the stories he’d heard there. In Ventura’s habit of making rounds of visits throughout the neighborhood, Mr. Costa discovered a way to theatrically explore and unify what would otherwise be disconnected personal histories and interactions contrasted with the community’s ongoing municipal euthanasia. The people who Ventura encounters all “act” their stories from a script compiled and parsed from their own biographies.

As he makes his rounds, Ventura searches the faces of the people he meets in the present for any signs of those he’s lost in the past. Vanda (Vanda Duarte), a recovering heroin addict, is a surrogate wife filling the yawning void left by Ventura’s spouse Clothilde, who left him with a knife wound and a broken heart and returned to Africa. Fellow Cape Verde exile Lento (Alberto Barros) plays cards with Ventura and memorizes a letter of reconciliation (cribbed from French poet Robert Desnos) he has asked the older man to compose for him.

Vanda and Lento, like Bete (Beatriz Duarte), a young girl who is utterly and unaccountably alone, and Paulo the Crutch, (Paula Barrulas) a panhandler a few hobbling steps ahead of his tragic past, are, in Ventura’s words, his “children.” To what degree that is biologically accurate the film does not make clear. But Ventura’s seniority in sublimated grief is undeniable. The government may be offering the people of “Colossal Youth” a “move for the future,” into clean, bright, and cheap new housing projects, but Ventura and his children are all irrevocably mired in the losses and unanswered questions of their pasts.

Mr. Costa used available light and a mini-DVD camera to photograph Fontainhas’ shacks, gutters, and rubble and the insides of the mostly barren new homes Ventura and his children are destined to occupy. The net effect of Mr. Costa’s compositions and alternately jarring and mundane soundscape of off-screen TV broadcasts, caged birds, and construction noises is so hypnotic that when a shot pans to reveal the sight and sound of cars rushing by on a freeway for the first time near the end of the film, it almost feels like a violation.

I’ve never seen low-resolution digital filmmaking yield such hypnotic, richly textured, and brilliantly and evocatively composed images as those in “Colossal Youth.” Mr. Costa’s alternately elegant, flat, dramatic, grimy, sterile, and off-kilter frames redeem even the most tortured and mundane banalities uttered by his cast. One’s mind will likely wander over the course of “Colossal Youth,” but an eye sympathetic to the symmetry and simplicity of truly inspired visual design will not be able to leave the screen for long.