Barnaby and Troy investigate the death of Agnes Gray, a middle-aged resident of Ferne Basset whose body is found floating in the river. The autopsy reveals that she was suffering from advanced cancer, but she was beaten to death with a metal bar. The police find her home ransacked and her clothes shredded. They also learn that she lived quite frugally and gave most of her money to charities. When Agnes's cousin Esslyn Carmichael dies on stage during a performance of the local theatrical society, Barnaby must determine what hidden secret has driven someone to murder.