I learned from him that this particular combine was not aware of the danger in which it stood, but that it realised that it must stand in some danger, so it had taken precautions. Since Christmas it had acquired hostages.

Here I interrupted, for I felt rather incredulous about the whole business. “I think since the War we’re all too ready to jump at grandiose explanations of simple things. I’ll want a good deal of convincing before I believe in your international clearing-house for crime.”

“I guarantee the convincing,” he said gravely. “You shall see all our evidence, and, unless you have changed since I first knew you, your conclusion won’t differ from mine. But let us come to the hostages.”

“One I know about,” I put in. “I had Mr. Julius Victor here after breakfast.”

Macgillivray exclaimed. “Poor soul! What did you say to him?”

“Deepest sympathy, but nothing doing.”

“And he took that answer?”

“I won’t say he took it. But he went away. What about the others?”

“There are two more. One is a young man, the heir to a considerable estate, who was last seen by his friends in Oxford on the 17th day of February, just before dinner. He was an undergraduate of Christ Church, and was living out of college in rooms in the High. He had tea at the Gridiron and went to his rooms to dress, for he was dining that night with the Halcyon Club. A servant passed him on the stairs of his lodgings, going up to his bedroom. He apparently did not come down, and since that day has not been seen. You may have heard his name—Lord Mercot.”

I started. I had indeed heard the name, and knew the boy a little, having met him occasionally at our local steeplechases. He was the grandson and heir of the old Duke of Alcester, the most respected of the older statesmen of England.

“They have picked their bag carefully,” I said. “What is the third case?”

“The cruellest of all. You know Sir Arthur Warcliff. He is a widower—lost his wife just before the War, and he has an only child, a little boy about ten years old. The child—David is his name—was the apple of his eye, and was at a preparatory school near Rye. The father took a house in the neighbourhood to be near him, and the boy used to be allowed to come home for luncheon every Sunday. One Sunday he came to luncheon as usual, and started back in the pony-trap. The boy was very keen about birds, and used to leave the trap and walk the last half-mile by a short cut across the marshes. Well, he left the groom at the usual gate, and, like Miss Victor and Lord Mercot, walked into black mystery.”

This story really did horrify me. I remembered Sir Arthur Warcliff—the kind, worn face of the great soldier and administrator, and I could imagine his grief and anxiety. I knew what I should have felt if it had been Peter John. A much-travelled young woman and an athletic young man were defenceful creatures compared to a poor little round-headed boy of ten.