You could say that these days Mexico is going through a period of tumultuous change. But really, Mexico has been in a state of constant change for the past century. Upheaval has become a way of life, and all the citizens can do is try to ride out the latest chaotic wave without getting pulled under.

Change is a central theme in Luis Alcoriza’s Mecánica nacional. Ostensibly the film is about a family that goes to the countryside for an overnight party that coincides with the finish of a cross-country race. In reality, it’s about a country that is evolving so rapidly that it’s not even sure of its identity any more. This is a portrait of Mexico in the seventies. The roads are jammed with cars, but all the cars are from America. The youth movement is going strong, and it’s clear these kids don’t share their parents’ values. Once the party starts, we hear the easygoing rhythms of traditional Mexican music clashing with the jacked up rhythms of rock n’ roll. Popular vocalist Lucha Villa is featured in a key role, but by the time she starts singing her character is so wasted that the song comes out as a tuneless groan. There’s a brief but fascinating exchange when a young Anglo woman, holding her camera ready, surveys the crowd looking for something to shoot. Her expression is perplexed, and after a few moments she says, “But there’s nothing Mexican here.” One of the partiers comes up behind her and says with a smile, “We are.” This is still Mexico, just not the Mexico she was expecting.

The movie opens at a large auto garage where family and friends are preparing for the picnic. One of the first things we see is a sign that says in bold letters “SOLO DAMOS SERVICIO A CLIENTES MUY MACHOS” (“WE ONLY SERVE CUSTOMERS WHO ARE REAL MEN”). In Mecánica nacional Alcoriza takes a long, hard look at his male characters, who try so hard to act like real men and end up coming off like foolish children. A few minutes into the film the garage owner and a truck driver are ready to fight each other over an almost meaningless verbal exchange. A gun is flashed, one guy stands down, and nothing happens. But the scene is important. These men spend a lot of their time trying to live up to a “macho” ideal that their culture has created. They just accept that you’re supposed to fight, drink and chase women. They don’t question it. That’s just the way it is.

Or that’s the way it used to be. Eufemio, the boss at the garage, is an ordinary guy trying to cling to the life he knows, but his world is falling apart. He heads off to the countryside with his wife, his mother and his two daughters, looking forward to a weekend filled with booze and cars. But in the course of a single night, he comes to suspect that his wife is unfaithful, he finds his daughter making out with her boyfriend, and his mother dies. Obviously, this would be a lot for anybody to bear, but Eufemio’s meltdown is mostly the result of his absurd notions about how things should be. The seething rage he directs at his wife and daughter seems insanely hypocritical since we’ve just seen him sneaking off in hopes of having sex with a hot-looking babe who’s been flirting with him. And while he’s awash in weepy sentimentality after his mother dies, we recall that this “saint” he’s mourning was a crotchety, obnoxious old lady who kicked the bucket after binging on food and booze.

Alcoriza has a real gift for handling actors. The film is overflowing with characters, and they’re all lively and entertaining. Mecánica nacional has a wonderful, chaotic spontaneity. The camera roams through the crowd allowing us to watch these people dance, drink, fight and flirt. As Eufemio, Manuel Fábregas may be pushy, lecherous, ridiculous, but he’s always human. As his wife, Lucha Villa swings from happy complacency to outraged hysteria and makes it all completely believable. Casting Sara García as the grandmother is a beautiful satiric joke. After years of playing saintly older women, García turns her film persona on its head by making the grandmother cranky, petulant and foolish. When the old lady dies and the family gathers round to say a rosary, their tearful devotion turns to anxious impatience as they realize they’re going to miss the cars crossing the finish line. After they’ve all run off, one by one, to watch the end of the race, we see the dead grandmother lying alone on the ground. The image is a blunt metaphor for a society that is ready to abandon tradition in favor of fast cars and color TV.

In a way Mecánica nacional seems like a Mexican version of Weekend. Aside from the obvious parallels, endless traffic jams and frustrated people getting into violent confrontations, both films are about societies coming apart at the seams. But unlike Weekend, the characters in Mecánica nacional don’t pick up guns to start a revolution. By the end of movie they’re so exhausted it seems that have no energy left for anything but to slide back into the routine of their lives. Like most of us, they really don’t want to confront the change they see in the world and try to deal with it. They’d rather go home and watch TV.

Released by Laguna Films. In Spanish. NO ENGLISH SUBTITLES.