Scandal breaks in the London press: There is a mole in the Intelligence Service! And it appears without a doubt, on a photograph taken by agents of MI 5, that the mole wears the face of Francis Blake! Mortimer is determined to believe that his friend has been forced to act against his will. But the initial investigations sweep away this hypothesis: Blake has opened, under an assumed name, an account fed by payments coming from the Bahamas. In a few months, he has withdrawn ₤30,000—more than 10 times his annual pay! With MI 5 agents planning to try Blake for high treason, or to kill him if needed, Mortimer decides to find his friend before they do. A long hunt begins …
À Londres, tous les médias s’emparent de « L’Affaire » : « Le Capitaine Blake, chef du M.I.5 de l’intelligence Service est recherché pour haute trahison ! ». Convaincu de l’innocence de son ami et soucieux de l’aider, Mortimer contacte un agent susceptible de le conduire jusqu’à lui. Pendant ce temps, « le traître » dîne en tête-à-tête avec Olrik.
Em Londres todos os meios de comunicação falam do caso."O Capitão Francis Blake, chefe do MI5, os Serviços Secretos, é procurado por todas as polícias por alta traição."Atordoado mas convencido da inocência do seu amigo, Mortimer tenta contactar Blake para o ajudar.Nesse mesmo momento "o traidor" janta com Olrik, agora chefe de uma rede de espionagem internacional.
