The man is the only bird who wears his own cage(L'homme est le seul oiseau qui porte sa cage)

A cold world full of people whose heads have been replaced by a cage filled with a rubber balloon. They cross paths with each other in the streets of an immense city. All these individuals resemble each other and live in a uniform way. Some, in an act of madness or lucidity, try to take flight with their balloon, but each attempt systematically meets with failure. But one person nevertheless finds a way to escape.