This book is apparently an extract from the author's earlier, much weightier tome 'Hitler 1939 - 1945: Nemesis' which has been published separately to co-incide with the imminent release of Brian Singer's new film 'Valkyrie'.
As a companion to the forthcoming flm it works very well in providing a brief, but reasonably detailed, description of Colonel Claus von Stauffenberg's failed assassination attempt of July 1944 and it's repercussions to those involved. In addition Ian Kershaw outlines a number of previous, and similarly unsuccessful, attempts on Hitler's life - some of which sound faintly ridiculous !
It will be interesting to see if Hollywood's portrayal of the main characters of the plot incorporate some of the moral complexities uncovered by Kershaw, if they do it will make the film a much more challenging one to watch.