• A brilliant new biography ... The book introduces crucial changes to ... the official version of events.

    Bryan Appleyard, Sunday Times
  • Engrossing, brilliantly researched ... The scale of Fuchs's spying was astounding, as were its consequences

    Jay Elwes, Spectator
  • He has delved into the archives to produce a remarkable story ... meticulous but highly readable

    Manjit Kumar, The Times