This book is designed to accompany the BBC series of the same title, broadcast this autumn, but like so many of the books that producer Laurence Rees has authored, it stands on its own as a thoughtful and thought-provoking introduction to many of the shadier deals of the Second World War, from the Nazi–Soviet Pact of August 1939 to the institutionalised distrust that marked the onset of the Cold War.

Rees has a big advantage over the mere historian. Not only has he been able to draw on a remarkable archive of oral testimony conducted over the years under his own auspices, but he can also say what he likes about it. Where historians pussyfoot around, Rees calls a spade