Winter 1984. After their train is hit by an avalanche in the alps, 30 year old Greta and five strangers find themselves trapped in the last car of a train, buried underneath the snow. On the radio they learn that a rescue operation is under way, but for some reason the last compartment seems to have disappeared from the face of the earth. As we follow their attempts to escape their icy prison, we begin to understand that there is more to the compartment than meets the eye...