A revolution in the Middle East has a direct and deadly impact upon the summer term at Meadowbank, a picture-perfect girls' school in the English countryside. Prince Ali Yusuf, Hereditary Sheikh of Ramat, whose great liberalizing experiment - hospitals, schools, a Health Service - is coming to chaos, knows that he must prepare for the day of his exile. He asks his pilot and school friend, Bob Rawlinson, to care for a packet of jewels. Rawlinson does so, hiding them among the possessions of his niece, Jennifer Sutcliffe, who is bound for Meadowbank.
Rawlinson is killed before he can reveal the hiding place - or even the fact that he has employed his niece as a smuggler. But someone knows, or suspects, that Jennifer has the jewels. As murder strikes Meadowbank, only Hercule Poirot can restore the peace.