As he promised himself, Philip Mortimer pays more attention to his friend Francis, when he thinks about it. If he noticed anything, it is that his friend has the gift of putting him at ease and making him forget everything that is not their conversation of the moment.
Like him, Francis is dedicated to his work. Probably more dedicated, actually. The professor might live in the same apartment as the head of MI5, but he barely meets him. They do not always work the same hours and they are often away on business travel. Certainly, they spend several hours under the same roof: each sleeping in his own room. The one place where they can really meet at is the Centaur Club - which Blake is a member of - when the latter invites him to dinner.
Life holds lots of work, little leisure, many acquaintances, distant friends and colleagues, and few relations still in touch. Since the departure of Nasir, who has returned to India, the Captain's only real attachment seems to be to Mortimer himself.
Francis is a man of action; always moving, always busy, never on vacation. As a friend, Philip Mortimer decides that it is his duty to remind his old comrade to take one from time to time, even offering to share his own. This seems to tempt the captain slightly more.
All that the professor deduces is that his friend cares for him. Well, that is mutual, he tells himself.
That's when the case arises. Times are troubled and cases related to espionage frequent. Often these cases involve former Cambridge students, old rivals for Blake, an Oxford man. Often the men under investigation lived their private lives in the shadows, illegally, unlike Blake – of so Mortimer had assumed.
When it all begins, Philip Mortimer is troubled. It only has been a few days since one of his mathematician colleagues died. Hero of the Second World War and pioneer of computer engineering, Alan Turing had himself been embroiled in one of these cases.
Soon after, Blake tells him he has a cousin who frequently contacts him with invitations to visit, a cousin he has already visited, and one Mortimer does not know about; a close acquaintance and he has never heard of her! Yet outside of his work, Blake tends to talk to Mortimer about the mail he receives. The professor is slightly wounded to hear of this cousin for the first time only now.
And then suddenly, the shock. Incomprehensible! Francis cannot have betrayed his country. Mortimer knows this in his whole being. His reason gives him excuses without end: there must be something else. Even when he discovers the money, evidence of his friend's guilt, the litany of alternative hypotheses does not stop. Still, there is another voice that overwhelms everything: Francis is in danger, you MUST find and help him.
His reason agrees: if one day he lost all moral sense, he would trust his friend to guide him. Blake is above all doubt; it is impossible that he has turned traitor. But it is what the other voice responds which bothers him: even if Francis were guilty - even if Philip would join him to be sold to an enemy country - if it could be useful to his friend, he would not regret going, even for a minute. What this means, Philip Mortimer prefers not to think about at all.
Then he decides to go find Blake, wherever his path leads.
