Perhaps no other aircraft in aviation history has been such a well-kept secret as the United States' Lockheed SR-71 Blackbird. This cutting-edge aircraft took the art of aerial spying to an unprecedented level and did it all from highly clandestine high-speed spy missions over Communist nations during the late 1960s and 1970s. With the help of breath-taking photographs, Mark Chambers tells the fascinating story of this truly unique aircraft's design and development as well as its famous and ingenious designer Mr Clarence 'Kelly' Johnson.