Francis Ford Coppola made four great movie masterpieces in a row in the commercial studio system — “The Godfather,” “The Godfather, Part Two,” “The Conversation” and “Apocalypse, Now.” He is probably the only living American filmmaker of whom that can be said.

He hasn’t been a commercial filmmaker in many years. That doesn’t mean, however, that the films he’s making now entirely for himself are great, or even convincing, cinematic art.

His film, “Youth Without Youth” from a Mircea Eliade novel and starring Tim Roth, was shown to critics here but never opened locally. Its box office in places where it did open was a tiny fraction of negligible. In a recent interview, a dazed and stunned Coppola admitted that “no one went to see it. No one.”

It was a baffling film.

So is “Tetro,” his new film starring many people’s nomination for Buffalo’s most regrettable celebrity native son, Vincent Gallo. Gallo, it turns out, is very good in the film, playing a troubled, surly and misanthropic American writer living in Argentina, a man whose depressed but stable life is thrown wide open when his younger brother comes to visit.

At first, he won’t even see the kid, a 17-year-old named Bennie who ran away from home to wait tables on a cruise ship. The writer’s common-law wife (Maribel Vertu of “Y Tu Mama Tambien”) matter-of-factly tells the boy “he really doesn’t want to know his family anymore.”

But blood is blood. Decency is decency. The writer eventually hobbles out of his bedroom with a cast on his newly broken leg (“I walked into a bus”) and the long-lost relatives are forced to spend time together.

Once upon a time, the writer was named Angelo. Now he insists on being called Tetro. “Angelo’s dead,” he says. So, he claims, is the writer he once was.

He is a cruel man — to himself above all (though the game is up when you see how he treats the woman he so clearly loves).

The film is in black and white, except for the flashbacks, which are in color. Students of Coppola films remember how brilliantly he used black and white in “Rumblefish.” In fact, the final hour of the film, when it leaves the clumsily Bergmanesque storytelling in Buenos Aires and hightails it out to Patagonia, is stunningly photographed.

Clearly, this is a deeply personal film. If you know anything at all about Coppola’s life, you know that his father, Carmine, began as a flutist in Toscanini’s NBC Symphony and became a composer himself (for some of his son’s films, among other things) as well as a Broadway conductor. And you also know that Coppola’s son Giancarlo died in a tragic boating accident, in a boat piloted by Ryan O’Neal’s son Griffin.

The paterfamilias of this film’s family is a world-touring conductor of minimal respect for his own children or his own brother. (His operative principal is “one genius in a family is enough.”) Traffic accidents — threatened and real — figure constantly in the film. Chance’s tragic malevolence is never far away.

All that personal resonance doesn’t change the fact that the film modulates from dourly and ineptly Bergmanesque to wildly, clumsily operatic. The tale itself is like something floridly Romantic in a 19th century way that a composer would turn into an opera or a ballet.

The film, ultimately, deserves to be called what some consider the most damning of faintly praising adjectives, “interesting.” Courtesy of the performances and camera work, it’s all of that. What it isn’t, though, is by any means good.

TETRO

Two and a half stars

STARRING: Vincent Gallo, Alden Ehrenreich, Maribel Vertu and Klaus Maria Brandauer DIRECTOR: Francis Ford Coppola

RUNNING TIME: 127 minutes

RATING: No rating but R equivalent for language, nudity and sexual frolic.

THE LOWDOWN: An ill-tempered, misanthropic writer in Argentina finds his life turned upside down when his younger brother visits from America.