A single mother (Halle Berry) lives with her two children in an isolated cabin in the woods. She tells her children that the outside world has been destroyed and that there are some dangerous supernatural monsters living in the forest. The only way to protect them is to tie them to the house tightly with several long ropes. The mother repeatedly warns the children never to loosen the ropes, but the children gradually begin to doubt whether the monsters really exist. Perhaps the real problem is their mother...