'Extraordinarily useful, endlessly interesting ... Jeffery captured the adventurous, John Buchan side of SIS with as much zest as he revealed the successes and failures of its analysis of events' (John Simpson
'A magisterial account of the two wars in particular, viewed via the prism of secret intelligence. Winningly, it also entertains' (Independent on Sunday
'Fascinating ... The book is full of examples of the ingenuity and courage shown by all ranks' (Douglas Hurd, Guardian
'Full of episode and personality, without ever succumbing to the swash and buckle that can dazzle those who get close to SIS' (Daily Telegraph
The first - and only - history of the Secret Intelligence Service,
written with full and unrestricted access to the closed archives of the
Service for the period 1909-1949.