In the heart of a city, the inhabitants of a tower wake up one morning to find that their building is shrouded in an opaque fog, obstructing doors and windows - a strange dark matter that devours anything that tries to pass through it. Trapped, the residents try to organize themselves, but to ensure their survival they gradually succumb to their most primitive instincts, until they sink into horror...
30-year-old factory worker Simon lives a solitary existence on a decrepit farm in the remote French countryside. Devoting his time to caring for his sister Estelle, who was left severely disabled when a childhood game went horribly wrong, Simon is plagued by guilt and depression. But he sees a way out, looking to otherworldly forces as a means of liberating both himself and his sister from the corporeal prisons in which they are confined.