In Cornwall, England, three members of the same family have suddenly died. Among the dead is Olivia, the reclusive writer whose war poetry gave Ian Rutledge a handhold on sanity while he fought in the trenches of France. Although no evidence indicates foul play, a concerned and influential relative suspects that the deaths are actually murders, and she convinces Scotland Yard to send someone for a thorough investigation. Rutledge's rival, Bowles, sees the Cornwall incident as an opportunity to get the shell-shocked World War I veteran away from London where a recent Ripper-style killing spree promises celebrity for the detective who can crack the case.
Accompanying the inspector to Cornwall is Rutledge's constant "companion" Hamish, the young Scot whom he unwillingly had to execute on the battlefield and whose tormenting voice sounds in Rutledge's head, forcing him to face unpleasant truths.