“You’re very silent, my boy,” he said. “Perhaps you’ve got something to think about, though. Something definite, I mean.” His tone changed. “God! What I would give to get my hands on the—the animal that killed John! I shan’t sleep till he’s caught. It’s torture he needs! Torture!” The kindly face was distorted. Anthony looked at him curiously. “The great difficulty so far,” he said, “is failure to find any indication of motive. I mean, you can’t do anything in a complicated case unless you can do some work from that end. A motiveless murder’s like a child without a father—damn’ hard to bring home to any one. Suppose I suddenly felt that life wouldn’t be worth living any longer unless I stabbed a fat man in the stomach; and I accordingly went to Wanstead and assuaged that craving on the darkest part of the Flats, and after that took the first train home and went to bed. They’d never find me out. The fat man and I would have no connection in the minds of the police. No, motive’s the key, and so far it’s hidden. Whether the lock can be picked remains to discover.” Sir Arthur smiled. “You’re a curious feller, Gethryn. You amuse while you expound.” He grew grave again. “I quite see what you mean: it’s difficult, very difficult. And I can’t imagine any one having a grudge against John.” Anthony went on: “Another thing; the messiness of the business indicates madness on the part of the murderer. With homicidal mania there might be no motive other than to kill. Myself, I don’t think the murderer was as mad as all that. Look at the care he took, for all his untidiness. No, the murderer was no more mad than the rest of the affair. It’s all mad if you look at it—in a way. Mad as a Hatter on the first of April. And so am I, by God!” His voice trailed off into silence. They had crossed the bridge now. Sir Arthur, instead of turning directly to his right to return to Abbotshall by the riverside path, chose the way which led to the village. Anthony drifted along beside him in unheeding silence. He was thinking. Yes, “mad” had been the right word to use. There didn’t seem to be any common sense about the thing. Even She was mad! Why swim to Abbotshall? The saving in time, he calculated, could have only been a matter of ten minutes or so. And she couldn’t—well, she must have been in hell’s own hurry. But the sandals indicated a bathing-dress, and surely the time taken to change into that might have been spent in covering the distance on dry land. And what had she been there for, outside that window of the study? She—surely She had nothing to do with that messy crime—must be interrogated. Oh, yes! His heart beat faster at the thought of seeing her again. He rebuked himself for thus early and immorally losing interest in his task, and returned to consciousness of his surroundings. He found himself in Marling High Street.