Captured in Libya in November, 1942, Kapitan Herbert Cleff was taken to the United Kingdom, following assessments that led his British captors to believe that he might prove useful to the Allied war effort. During interrogation, Cleff kept releasing tantalizing snippets of information about the progress that the Germans were making with jet-powered aircraft propulsion and unmanned offensive missiles. Cleff enjoyed being center of attention, but who was he? Looking for answers, Brian Brinkworth also assesses the truth of Cleff's occasionally unproven claims.