Hitler's followers seek a postwar nuclear revenge in this intriguing if uneven technothriller by the author of Shadow Man (1988) and Oppenheimer: The Years of Risk (1982), and co-author (with Whitley Strieber) of Warday (1984). It is 1991, and a crew of London construction workers have uncovered an oddlooking relic of WW II--a metal cylinder similar to a cannon's barrel, sealed off at the ends so that it resembles a primitive bomb. Brought in to investigate, soon-to-retire Deputy Home Minister Edmund Ramsden finds himself inexplicably fascinated by the forbidding object. When it turns out to be the unloaded shell of a crude, German atomic weapon, Ramsden is naturally appalled, and begins scouring M-15's WW II records (particularly the largely absent top-secret ""Archbishop files"") for any knowledge within England of the bomb's existence. Cut to Los Alamos, 1945, just before the July testing of the US's own atomic bomb. Physicist Philip Cavanaugh, one of Little Boy's designers, is unexpectedly called into service by General Groves, military director of the Manhattan Project. Sent undercover into Germany's Russian-occupied sector to investigate evidence of a secret Nazi munitions factory, the ingenuous Cavanaugh discovers, to his horror, both primitive versions of his own atom bomb and a Nazi plot to nuke the Allied capitals after Germany's fall. Cavanaugh's race to save London, Moscow, and Washington from nuclear destruction (and Ramsden's pursuit, in modern times, of the truth behind the long-suppressed Archbishop files) makes for a gripping plot when technical explanations and surprisingly wooden historical figures (Oppenheimer, Groves) don't get in its way-but the author's hasty wrap-up may leave readers bereft just when the excitement starts. Still, overall, chilling entertainment--solidly grounded and ultimately satisfying.