When Hugh finds a scribbled note in Toby's oesophagus during post-mortem, he contacts controversial DCI Thirsk and refers the untimely death to the coroner. In a neighbouring hospital, a ninety year old woman dies, and with a million pound inheritance going solely to one son, the other son suspects foul play and demands a post-mortem. A pulmonary embolism is the cause of death, which is inconsistent with her lifestyle, and the case is also referred...