A tragedy occurred in the wealthy and respected Cornish Trevelyan family: Nicholas and Olivia, half-brother and sister, committed suicide, and soon their brother Stephen dies in an accident. A distant relative of the Trevelyans does not believe that Nicholas died voluntarily, and contacted Scotland Yard asking for a thorough investigation. The case has been assigned to Inspector Ian Rutledge. The inspector learns that Olivia, under a man's pseudonym, wrote poems that he read at the front, and that for many years her loved ones have been dying under strange circumstances. Rutledge realizes that a family secret is encrypted in Olivia's poems, and decides to get to the bottom of it at all costs...