Eccentric Cambridge archaeologist Horatio Smith takes a group of British and American archaeology students to pre-war Nazi Germany to help in his excavations. His research is supported by the Nazis, since he professes to be looking for evidence of the Aryan origins of German civilisation. However, he has a secret agenda: to free inmates of the concentration camps.
Leslie Howard is on good form here as the outwardly fastidious academic with a secret to keep. He decides to offer some of his students an holiday trip to Germany (just the boys!) so they can try to establish once and for all whether there was an "Aryan" race there. Quickly we discover he also has an hand in rescuing many creative and scientifically minded for the evil clutch of the Nazis and their chocolate eating boss "General von Graum" (Francis L. Sullivan). As the students get in on the act, it's the American "David" (Hugh McDermott) who is most itching for action and it's also him who falls for the charms of "Ludmilla" (Mary Morris) who is treading a very dangerous path trying to save her imprisoned father whilst not betraying this updated iteration of Howard's "Scarlet Pimpernel". There's some lovely writing here - especially from the swastika wearing propagandists who insist that their nation is the ideal place to live and work. As the story progresses, there becomes something effectively sinister about the denouement and the battle of wills between Howard and a very much on form Sullivan that delivers one of the more memorable wartime thrillers.