"You've got to George! I can't tell you everything over the public air. But I've seen _him_: He's diabolical. I know it now!" _Him_! It could only mean, of all the world, one person! "He's here!" he went on. "Near here. We saw him today! I didn't want to tell you, but that's why we came. It seemed a long chance, but it's he, I'm positive!" I was staring at the image of Alan's eyes; there was horror in them. And his voice too. "God, George, it's weird! Weird, I tell you. His looks--he--oh I can't tell you now! Only, come!" * * * * * I was busy at the office in spite of the holiday season, but I dropped everything and went. By one o'clock that afternoon I was wheeling my little sport Midge from its cage on the roof of the Metropole building, and went into the air. It was a cold gray afternoon with the feel of coming snow. I made a good two hundred and fifty miles at first, taking the northbound through-traffic lane which today the meteorological conditions had placed at an altitude of 6,200 feet. Flying is largely automatic. There was not enough traffic to bother me. The details of leaving the office so hastily had been too engrossing for thought of Alan and Babs. But now, in my little pit at the controls, my mind flung ahead. They had located him. That meant Franz Polter, for whom we had been searching nearly four years. And my memory went back into the past with vivid vision.... * * * * * The Kents, four years ago, were living on Long Island. Alan and Babs were fourteen at the time, and I was seventeen. Even then Babs was something kind of special to me. I lived in a neighboring house that summer and saw them every day. To my adolescent mind a thrilling mystery hung upon the Kent family. The mother was dead. Dr. Kent, father of Alan and Babs, maintained a luxurious home, with only a housekeeper and no other servant. Dr. Kent was a retired chemist. He had, in his home, a laboratory in which he was working upon some mysterious problem. His children did not know what it was, nor, of course, did I. And none of us had ever been in the laboratory, except that when occasion offered we stole surreptitious peeps. I recall Dr. Kent as a kindly, iron-gray haired gentleman. He was stern with the discipline of his children; but he loved them, and was indulgent in many ways. They loved him; and I, an orphan, began looking upon him almost as a father. I was interested in chemistry. He knew it, and did his best to help and encourage me in my studies. There came an afternoon in the summer of 1966, when arriving at the Kent home, I ran upon a startling scene. The only other member of the household was a young fellow of twenty-five, named Franz Polter. He was a foreigner, born, I understood, in one of the Balkan Protectorates; he was here, employed by Dr. Kent as laboratory assistant.