Opening titles appear over beautifully toned flooring tiles. The lazy chatter of mid-afternoon activity sounds from nearby streets. Soapy water sloshes over the tiles and soon an airplane reflects through the middle of the frame. A great movie begins.

Cleo (Yalitza Aparicio) is our protagonist—though it takes us awhile to realize it. She is a live-in maid working for a middle-class family in Mexico City. Along with her counterpart, Adela (Nancy García), she prepares the family meals, cleans up after the family (and the dog—which we later realize was the ugly activity behind the opening title sequence), and puts the kids to bed. All of the four children love her, but she seems to share a special connection with the youngest boy, Pepe (a brilliant Marco Graf, who displays such disregard for the camera we can’t help but recognize the imaginative innocence of childhood).

Roma is packed with little details that make it full of life. Its black and white photography seems especially able to reveal beauty in what would otherwise be mundane human existence. That writer-director Alfonso Cuarón shot the film without a cinematographer is particularly remarkable. There are breathtaking slow pans, framings that ought to be hanging in a museum, and images that will not soon be forgotten.

It would be easy to overlook the screenplay of such a visual picture, but Roma’s is worth commending. All its little details were first written by Cuarón. So too were its characters—who at times appear as stark and indelible as its visuals. The husband/father (Fernando Grediaga) and Cleo’s romantic acquaintance, Fermin (Jorge Antonio Guerrero), are simply and quite obviously asshats of the lowest order. So contrast are the wife/mother, Sofía (Marina de Tavira)—who acts and reacts with such obvious humanity we can’t help but empathize—and, of course, Cleo—whose quiet demeanor and guarded existence leaves us searching for her identity almost as much as she does.

As much as Roma belongs to Aparicio and her incredible performance, it is all the more the unmistakable product of Mr. Cuarón. Here again, he uses that signature technique of his to create two unforgettable sequences. Instead of cutting away to close-ups and other angles when the film erupts into madness and action, Cuarón keeps it all right there, staged within the bounds of the existing frame, unraveling without a cut to an alternative take. Such is life, and such is the cinema of one of the all-time greats.