Matthew Pelham's disappearance, while flying an RAF Harrier, can only be explained through investigations conducted some forty years apart. The quest involves wartime intelligence services, high politics in the Third Reich and beleaguered Britain, and has incalculable implications for the war's course and future events. In 1940, MI5 specialist Marcus Gifford has a new case that compels him to think the unthinkable. Urging a dramatic change in military policy draws Gifford into the highest political echelons and risks terrible retaliation from Göring's Luftwaffe. Himmler wishes to thwart Gifford and recover a priceless lost asset for his Führer. In 1982, Dr Richard Pelham grieves for his lost son and is determined to remove from Matthew the taint of official blame. Pelham's loss and wartime memories are made raw again by an old photograph, one with an incredible image. The more he questions the murkier the answers seem. The photo must be a fake, but to what purpose, and why did Patrick Millburn, a complete stranger, deliver it? MI5 knows more about the entire mystery - much more. The temporal jigsaw undermines precepts of history and dangles a tantalising prize for Britain.