Yezhov means ‘Hedgehog’, although Stalin called him affectionately Yezhevichka, ‘little bramble’. Despite the implicit prickliness, there was momentary relief in the USSR when, in autumn 1936, Stalin appointed N I Yezhov head of the NKVD, as the secret police was then called. It seemed that at last a series of Polish gentry (Dzierżyński and Menzhinsky) and a Russian Jew of Polish origin (Yagoda) had given way to a diminutive working-class Russian lad, a friendly, sociable troubleshooter.

Within weeks this illusion was shattered: in the next two years Nikolai Yezhov despatched more people to torture and execution than possibly anyone in human history, and created an atmosphere of all-pervading terror that crippled the nation’s psyche for generations. Not until autumn 1938, when Stalin brought Lavrenti Beria to