Summer, 1997. Twelve-year-old Grace and eleven-year-old Asta have been friends for as long as they can remember. When her father suddenly leaves, Grace’s fascination with religion and the supernatural becomes an obsession. At the end of the school holidays, the girls go to stay in a cottage in the Cornish countryside with Asta’s bohemian mum, Kate. There, troubled Grace is forced to confront her demons...