A mother and father contemplate sending their oldest daughter to London to study.

It’s 1970 and the family lives in Rio de Janeiro. Brazil has been under a military dictatorship for years. the daughter is college age, rebellious, and the country is enduring a crackdown brought on by the kidnappings of foreign ambassadors. The kidnappers want political prisoners, who are many, freed in exchange for these diplomats.

But the father, Rubens (Selton Mello) wonders if Veroca needs to be abroad, just “until this phase is over.”

Is he discussing Veroca’s (Valentina Herszage) latest “phase?” Pot-smoking, music-obsessed and outspoken? Or are he and wife Eunice (Fernanda Torres) pondering the latest “phase” of an oppresive, arrest-everyone/interrogate thousands/detain hundreds government run by an unaccountable army and pistol-packing plainclothes secret police?

“I’m Still Here,” the latest film from Walter Salles (“Central Station”), is a chilling history lesson where what’s being taught here in Portuguese (with English subtitles) speaks to the universal concern of what happens to civil liberties in a time of oppression, when an authoritarian government controls the military, the courts and the media and can brand anyone it wants a “terrorist,” “murderer” or undesirable.

Salles folds a portrait of a comfortable life, albeit with armed soldiers everywhere, into this story of one family’s trial by secret arrest.

Rubens is an engineer — a designer who has planned a new house for them that he’s laying out on a gorgeous piece of land with a view of the Christ the Redeemer statue overlooking Rio. The family has a car, the leisure for trips to the beach, and has a live-in housekeeper to help clean up after and feed four girls and a little boy.

But Rubens used to be a legislator. And he’s not totally muzzled his “Death to the Dictatorship!” sensibilities. He takes mysterious calls and deliveries. And early one weekend morning, the dead-eyed goons with pistols stuffed down their pants show up and take him away.

“Your husband will be home soon,” they lie. Three of them stay behind to search the house, monitor the phone and intimidate one and all. The others hustle Rubens into a VW Beetle — the cop car of choice — and off he goes.

He wasn’t the first. Veroca faced an alarmingly aggressive gunpoint stop and search on the drive home from the movies with friends. Soon, the ever-questioning and pleading Eunice will have her moment — with a younger daughter — stuffed into a VW, handcuffed and hooded and hauled off for questioning.

Salles builds his film on fear — when the police arrest everybody, they have mug shots of everyone, which they show Eunice to see if she sees “anyone you recognize” — and the aching uncertainty of not knowing.

Unaccountable to anyone, authoritarians don’t even admit they’ve arrested someone, much less the “charges,” their status and location.

Eunice has one daughter in Europe and other kids to keep safe at home, a house to keep with a sexist banker who won’t let her access their accounts without her absent husband (she can’t say he’s been arrested) and a lie to maintain for those kids even as friends and others struggle to question and plead for “justice” that they have to know won’t be coming. Not for years, decades even.

Salles’ film takes place in 1970, 1996 and close to the present day as brief epilogues update on what everyone has done or become and the status of their “case.” “Closure” always hangs out there, in the distance, where no justice can be found. But Mom hung on, and son Marcello (Antonio Saoia) grew up to tell their tale in print.

What’s most chilling here is what we don’t see, the distant screams in the prison, the one young guard who won’t say where her husband is, but who tells her “I just want you to know that I don’t approve.“

We hear the drilled dehumanization chants of soldiers in training, an army that exists to control, suppress and oppress the people. We rattle through city streets in tiny cop cars with sirens blaring, remembering the days when VW stood for “the Very Worst car” to have an accident in.

I found the final chapters less moving than intended, and the epilogues anticlimactic — one more than the other.

But Torres is so subtle at portraying a mother unable to show panic or righteous rage that when Eunice finally does let her guard down it’s almost shocking. It’s a great performance and worthy of the Oscar nomination she earned.

The film is also up for Best Picture and Best International Feature at the upcoming Academy Awards. It’s good enough to contend, even if we know that the film’s cautionary message about enduring the democratically unendurable, is what got it nominated. A lot of filmmakers in a lot of countries are thinking about that these days.

Rating: PG-13, violence, marijuana, smoking, nudity, profanity

Cast: Fernanda Torres, Selton Mello, Valentina Herszage, Bárbara Luz, Cora Mora, Guilherme Silveira, Antonio Saboia, Luiza Kosovski and Fernanda Montenegro,

Credits: Directed by Walter Salles, scripted by Murilo Hauser and Heitor Lorega, based on a book by Marcelo Rubens Paiva. A Sony Pictures Classics release.

Running time: 2: 17