A virus has ravished the world. Paul (Joel Edgerton) his wife Sarah (Carmen Ejogo) and their son Travis (Kelvin Harrison Jr.) all live in their house in the woods. They have rules to protect themselves from the virus and other people.

They capture a man trying to break into the house. After tying him up outside overnight to make sure he doesn’t have the virus they find out that the man, Will (Christopher Abbott) has a wife and son and he was looking for water for them.
Sarah suggests letting Will and his family live with them. Paul goes over the rules. The front door always stays locked and only Paul and Sarah have a key. And no one goes out at night.
One day Travis’ dog runs off into the woods. Travis thinks he hears something out in the woods. One night Travis gets up and finds the front door unlocked and open. Travis’ dog returns sick the virus. They kill and burn it. Then Travis reveals that the door was open.
This is a pretty cool low key thriller. Director Trey Edward Shults crafts a quietly intense film where there are no monsters, just people and the unknown.