After drugs and syringes are discovered stolen from a local veterinary surgery owned by Raif and Georgina Canning, a local woman is found dead next to her swimming pool, killed by an overdose of barbiturates. When Raif Canning and Adam Keyne -- men who discovered the body -- are found murdered as well, Barnaby and Troy must weed through a dark world of adultery and lies to uncover the identity of the calculating perpetrator. Their efforts reveal a woman who places more importance on her social prowess and status than the life of her lover. Guest star: Lucy Punch (Doc Martin; Hot Fuzz)

The town of Causton's detective chief investigator and his detective sergeant investigate the scandals and deadly deeds that lurk just beneath the well-manicured surface of the county of Midsomer. The series is bolstered by a rotating cast of investigators and many special celebrity appearances.