Grace (Nicole Kidman) lives in semi-seclusion on a remote island with her two children, awaiting her husband's return from the war.
Both children suffer from a rare form of photosensitivity which renders them open to harm from natural light.
Thus the trio live in almost perpetual darkness within the house, according to a harsh but life-preserving set of rules that their mother has designed for them.
When looking after the children by herself proves too much, Grace hires in some rather mysterious servants.
Suddenly there seems to be more to the old house than Grace had previously sensed and a chilling descent into fear and paranoia begins.