He was making no secret of his conduct.

He was serving the Allies.
"And that is the reason you are hunting me up; that is the reason that you have arranged this interview, probably at the instigation of your friend, the doctor.

You wish to employ me for a second time as the secret instrument of your espionage.

'Captain Ferragut is such an enamored simpleton,' you have said to one another.

'We have nothing to do but to make an appeal to his chivalry....' And you wish to live with me, perhaps to accompany me on my voyages, to follow my existence in order to reveal my secrets to your compatriots that I may again appear as a traitor.