When in March 1938 Germany invades Austria, all anti-Nazis are immediately rounded up and imprisoned. Prominent amongst these is liberal editor Johann Fehrbach, his Anglo-Irish wife, and his two daughters. But the elder of the girls, 17-year-old Annaliese, is separated from her parents and taken into Gestapo custody.

The officer arresting her has immediately recognized that she is an exceptional personality: Extraordinarily good-looking, she has an IQ of 173, is a superb athlete, head girl of her convent, and, because of her mother, speaks English fluently. Annaliese is taken off to an SS training camp and after an exacting and often terrifying learning process, is inducted into the SD, the most secret of German secret services.