Like Francois Truffaut’s “The 400 Blows,” Mexican writer-director Alfonso Cuaron’s “Roma” employs black-and-white footage shot in sweeping, extended takes to evoke an almost documentary feel, even as he hearkens back to his own childhood.

For Cuaron, that means returning to the Colonia Roma neighborhood of Mexico City — the family house he shot “Roma” in is located directly across the street from his real-life childhood home, the street address only one number apart — with a story set in 1970-71.

Cuaron’s protagonist is Cleo (Yalitza Aparicio), one of two live-in maids at the middle-class household maintained by Sofia (Marina de Tavira), the mother of four children. Her marriage to a doctor, Antonio (Fernando Grediaga), proves as ill-fated as Cleo’s brief romance with an avid young martial arts enthusiast, Fermin (Jorge Antonio Guerrero).

While the family can afford a comfortable lifestyle, and even a working-class servant like Cleo is afforded conveniences such as high-quality health care, Cuaron never lets us forget the tenuousness of the family’s relative affluence.

At first, the signs are small and almost comedic, such as the pet waste that Cleo is constantly cleaning up in the house’s narrow-gated driveway because there are no places outside where the family dog can safely be allowed to run and play.

As Antonio’s absence from the home grows longer, though, Sofia tries to hide the evidence of the financial and emotional strain it’s placing on her by taking the family to celebrate the winter holidays with their more wealthy “gringo” relatives.

The disparity in living standards between these partying families and their overlooked “help” is underscored by their proximity. The maids and other servants live in next building over from the bedrooms of the children whom they spend as much time raising as do the kids’ parents.

We see how fragile this layer of privilege is when Cleo and Sofia’s mother are caught out in public during a massacre of student demonstrators during the Mexican Dirty War in Mexico City in 1971, and medical care suddenly becomes very scarce.

Cuaron doesn’t end “Roma” with his characters surveying the tides on the beach, as Truffaut did “The 400 Blows.” Instead Cuaron stages the characters’ denouement on a beach of his own, as Sofia realizes Cleo is more than someone who looks after her family, and is actually part of her family.

Cuaron loves 360-degree camera pans, which allow viewers to breathe in the atmosphere of his settings, whether they are open-air courtyards surrounded by buildings, riots in the city streets, waves threatening to tow the children under, or the empty home after a parent has left for good.

While the era and the country obviously are not our own, they differ from those of other historic period pieces or foreign films in that they are close enough to our own modern-day circumstances to feel haunting.

What happened there can happen here.