Mexico has made some progress over the past decade in raising incomes for the very poor, which means that overall inequality has decreased. But the top 20 percent of the population still earn 53.4 percent of the total national income, according to statistics from the Economic Commission for Latin America and the Caribbean. The 40 percent of the population below the wealthy, the segment where one would expect to find the middle class, make 33.6 percent of national income.

“The middle class here does not exist,” said Ana Suárez, a 27-year-old lawyer who pronounced the movie “the absurd of the extremes of the two classes.”

“The children of the upper classes don’t know how to do anything, except party,” said Arturo García, 44, a collections agent, who enjoyed the movie. “I have dealt with people like that at work. We call them ‘daddy’s children.’ ”

Mr. Alazraki, the movie’s director, admits to bearing a passing resemblance to the Noble children himself. As in the movie, his father, Carlos Alazraki, is a self-made man, having built a career as an advertising executive. The younger Mr. Alazraki recalls how furious he became when his father announced that he would not get a new car until he got into college.

“It happens to most parents that want to give their children all the opportunities that they never had so that they never struggle the way they did,” he said, “without actually realizing that the character that comes out of the struggle is what helps you succeed.”

Midway through college in Mexico, he transferred to the University of Southern California, where he took film courses and worked as a studio intern, learning what it was like to be a relative nobody. Unlike his Mexican circle, his Los Angeles friends were all taking odd jobs to make ends meet.

He said he had changed once he returned to Mexico. “I could see a big difference between the friends that left the nest and the ones that didn’t,” he said. “The ones that didn’t never lost their sense of entitlement and grew to turn, some of them, into despicable people.”