Sidney is called on to investigate the unexpected fall of a Cambridge don from the roof of King's College Chapel; a case of arson at a glamor photographer's studio; and the poisoning of Zafar Ali, Grantchester's finest spin bowler, in the middle of a crucial game of cricket. As he pursues his quietly probing inquiries, Sidney also has to decide on the vexed question of marriage. Can he choose between the rich, glamorous socialite Amanda Kendall and Hildegard Staunton, a beguiling German widow three years his junior? To help him make up his mind Sidney takes a trip abroad, only to find himself trapped in a complex web of international espionage just as the Berlin Wall is going up.