A strange and deadly mist envelops Paris. A group of survivors finds refuge on the upper floors of apartment blocks and on the roofs of the capital. With no information, electricity, food or water, a couple attempts to survive this disaster and save their daughter… But as the hours go by, one thing becomes quite clear: there is no help on the way, and if they want to make it through this catastrophe alive, they will have to try their luck in the mist…

Infection takes place in a dark, isolated hospital, where one doctors mistake has led to dire consequences for a patient. In a hospital death is just a breath away.