Snowpiercer, a science fiction movie playing in limited release in the US is one of the best movies about class stratification I've ever seen.
A short (no spoilers) synopsis:
In the near future, humanity finally responds to global warming with some sort of cold bomb which results in the entire earth being frozen over. No life remains, except for passengers on a self-sustaining train that circles the earth.
The train is divided by first, second, and third class passengers - all depended on which tickets were bought before the big freeze. The third class passengers live in squalor in the back, the first class live in luxury at the front, and the second class passengers act as servants and police. 17 years after the big freeze, the 3rd class plots a revolt.
The central action of the film is the rebels fighting their way through the train. The film is based on a French graphic novel, and the stylized visuals reflect that graphic styling. There's a lot of violence - brutal, pointless, and often counter-productive. It's not the pretty, bloodless violence of a Michael Bay explosionfest. It's up-close, personal, and not without cost.
The theme of class is not explicitly questioned. But the viewer is left wondering: if there was enough for the first class to live in spoiled, self-indulgent luxury, why did third class need to live in such oppressed squalor? Couldn't they have divided up the assets so everyone could live moderately well? Why did a ticket purchased 17 years ago determine a passenger's fate? Why did children of the first class passengers deserve the benefits of their parents first class ticket?
I have a lot of quibbles with the movie, including a major reveal at the end which made no sense at all. But I was pleased to have the film explore the questions of inequality that are hardly ever mentioned. Why are the rich entitled to a lavish lifestyle while others starve? Why do we accept inequality as fated? Why do we stick to our place? Why is luxury or squalor a birthright?
Without spoiling, I found the ending satisfying overall. A good mix of nihilism and hope.