Masterpiece Mystery!
Hercule Poirot: Series IX: Cat Among Pigeons (2x4)
:
Miss Bulstrode, the elderly headmistress of an English girls' school, is warned by a parent that she has recognized someone at the school from her days in the intelligence service. And then there is a murder, and Poirot is on hand to try to solve it.
Poirot finds connections with a revolution in the Middle Eastern kingdom of Ramat and Prince Ali Yusuf's missing jewels.