《骇人命案事件簿 第十五季》讲述的是：　　When Bentham DeQuetteville falls to his death from a roof after seeing a headless horseman, his aristocratic family seem more concerned about their forthcoming Civil War re-enactment than the incident. As Barnaby and Jones try to find out the truth behind the ghostly figure, their investigation uncovers shocking secrets about the DeQuettevilles.