Retreat features some sweeping exterior shots and action, but for the most part it stays contained within a single home on an isolated and otherwise empty island. Martin (Cillian Murphy) and Kate (Thandie Newton) have come here to get away from the hustle and bustle of life and to try to deal with a recent, undisclosed rift between them. They’ve had happy times at this cabin in the past and are hoping to recapture that magic, but their attempts at reconciliation are interrupted by the arrival of a battered and bloodied man named Jack (Jamie Bell) who they find unconscious and armed outside. Their act of kindness is soon punished with unwanted knowledge when he awakens and shares what brought him to the island. It seems a deadly and unstoppable virus has begun ravaging the outside world, and their only hope of survival is to seal up the cabin until the airborne danger has passed. The island has no telephone access. The CB radio they’ve previously used to contact the mainland is strangely silent. And Jack strongly insists both for their safety and his that they follow his instructions. And a man with a gun can be fairly convincing…