Franck has been studying for the French equivalent of an MBA, so is sent to his home town for an internship in the assembly plant where his father has worked for 30 years.
We can see it coming: the dynamic between boss and worker.
But this gets much deeper. Here we might see our own lives, whether we work in retail, or management, or anything most people do for a living in "developed countries." We see a world that, while it's supposed to be Great Progress from naive feudalism, is, essentially, Feudalism (with a capital F)! We pretend it's a game, but when everyone plays it, when the system is so deeply ingrained in is (from birth, as is Franck's case), it's as real as the coffee in your pot. Respect the Hierarchy! The bishop, the Earl and the Baron all work upstairs with the computers, while the serfs toil in the fields, quietly and honestly Doing Their Part.
In this case, some toil in order for their children not to have to. But they do; just from another side of the glass, as much a slave to the system as the father. What does this indoctrination do to children? What does it teach children about the worth of the work, or of the worker?
The intensity with which the film displays the core issue at hand may very well capture the most hardened among us. It may even shame some of us.
Watch only if you are willing to, well, "take a long look at your whole scene," to quote another film. I saw mine.