In 1920s England the life of Sarah Piper, a young woman of limited means and even less experience, is changed when she is sent to assist a ghost hunter, Alistair Gellis--rich, handsome, scarred by World War I, and obsessed by ghosts--has been summoned to investigate the spirit of the nineteen-year-old maid Maddy Clare, who is said to haunt the barn where she committed suicide.