Father Brown - Season 2 Episode 8

Ex-colonel Gerard is poisoned after arguing with his nephew Edward. Edward is a former POW from Korea and the colonel claims he has been brain-washed but Edward sticks to his story that Gerard killed his father in order to marry his widow Ada. None of the household – including Ada's brother Rupert and his adopted daughter Jia-Li – seem upset at the colonel's death and each had a motive for murder. Then Father Brown is poisoned – hopefully he can recover in time to unmask the killer.