No; evidently the matter involved some great State secret, concerning which the Prime Minister had sought the confidence and assistance of his daughter. Yet Westerham could not altogether understand how this might be, because he could not conceive any matter of State which it would not be better to trust to the Secret Service than to a young girl. Whatever it might be, the mystery embraced Lady Kathleen; and with the single-hearted desire to assist her, Westerham determined, whether it pleased her or not, that he would range himself on her side. To do this, however, it would be necessary to discover what the mystery was, and he was still far from the solution when he fell asleep. On the morrow he rose early, and sat till lunch-time in the reading-room holding a paper before him, but in reality setting up and then demolishing a thousand and one theories to account for Lady Kathleen's plight. He had sent for Melun, and while he waited for him he debated with himself as to whether or not he should tax the captain with complicity in the matter. Finally he decided against such a course, seeing that an affair of such a magnitude as that in which Lady Kathleen was entangled must of a certainty outweigh in value even the great financial inducements with which he had sought to attach Melun to himself. Finally Sir Paul resolved to cease his exploration of London and begin his exploration of the devious paths of Captain Melun, with the turnings and twistings of which he was still unacquainted. It was quite possible that for the better conduct of his campaign against the Prime Minister Melun might require a certain amount of ready money, and in return for that ready money the captain might be led into showing Westerham sufficient of his life to enable the baronet to grasp and understand the mystery of Lady Kathleen. When at last Captain Melun came up after lunch Westerham greeted him coldly—so coldly that the captain raised his eyebrows. “It seems,” he said, “that you are not in a very good humour. Is London beginning to bore you?” Sir Paul looked at him sharply. “No,” he said, thoughtfully, “not in the least, though I confess that I have to some extent exhausted its ordinary attractions. Now I propose to plunge a little deeper into its secrets and its mysteries. In this direction I am, of course, looking to you to help me.” The captain nodded. “Quite so,” he agreed, “but I hope you realise that up to the present I have had nothing but your promises of favours to come—and times are hard.” For answer, the baronet took out his pocket-book and counted out ten one-hundred-pound notes upon the table. “This,” he said, “should be a sufficient guarantee of my good faith for the present. Mark you, I have had some experience of your kind before, and I do not propose to pay down a lump sum for services which you may subsequently find it inconvenient to render.