Sergeant Clegg assumed an air of profound sagacity, which did not altogether become him too well. At the moment he was a prey to conflicting emotions. A police-officer’s career in an obscure Berkshire village doesn’t get too many chances for personal “spot-light.” And although he felt that his big chance had come, he had a nasty feeling somewhere at the back of his mind that the case was going to prove _too_ big. However, he turned to the son of the murdered man and to the Doctor who had accompanied him into the library and made his preliminary announcement—importantly! “Nothing in here must be touched. Nothing—whatever.” “Nothing has been disturbed, Sergeant Clegg. Doctor Gunner arrived only a few minutes in front of you.” “That’s all right, then, Mr. Stewart! You might make your examination, Doctor, with as little disturbance of the corpse as possible—will you? I haven’t got a photographer handy—that business will have to come later.” The murdered man was seated in a chair at his desk—the cause of death being painfully visible to all. He had received a heavy blow or blows from behind—the back of his skull was smashed like an egg-shell. He had apparently been in the act of writing when killed—for his pen had almost entirely fallen from his grasp—the butt being just retained between thumb and forefinger. He was dressed in a dark-blue dressing-gown and on his feet were bedroom slippers. The dressing-gown had been put on over his pajama sleeping suit and he gave every appearance of having come downstairs from his bedroom. The doctor busied himself for a few moments over his gruesome task. Meanwhile the Sergeant turned to the young man who found himself so suddenly bereaved. He cleared his throat—twice. “Tell me the details, Mr. Stewart, as far as you are able.” Stewart shook his head. “I know very little. The maid who does the library every morning was amazed this morning to find the door locked. She couldn’t understand it, so she informed Butterworth, the butler. He went along and found that what she had reported was correct. He sought me out and we found Mr. Llewellyn, my father’s secretary. We went to my father’s bedroom. It was empty—the bed had not been slept in. So we decided to burst open the library door. You can see for yourselves how we found my father. I immediately telephoned for you and for Doctor Gunner.” “The door was locked, you say. Where was the key?” “In the lock—on the inside.” Clegg strolled across to the French doors that opened on to the garden. “These are fastened all right. All the bolts are shot.” He stooped down and examined them. “By gum—that’s funny. How did the murderer escape? Bit of a puzzle—eh?” Stewart saw the drift of his remarks. “Extraordinary, isn’t it?” he ventured. Clegg walked over to the desk and looked at it carefully. Beside the dead man’s hand there rested a sheet of notepaper. The Sergeant took it up. “Looks as though this is what he was writing when the blow fell,” he suggested.