Death-Watch by John Dickson Carr

who killed him.”
    “Good Lord, no! That’s what I wanted to tell you … I only know who didn’t kill him. Although I wish they had killed him, and then we could have disposed of the lot. Still, as Don is my first client”— suddenly a harsh smile flashed across her face—“I may be able to institute proceedings for him …” She stepped inside the door, threw it open, and spoke outside. “Come in, Mr. Boscombe. This will interest you.”
    “ What the devil —!” shouted a bewildered Hadley.
    “It’s funny enough,” said the girl, “and low enough, and mean enough, to be a fit end for Ames. It has a nasty sort of simplicity about it. Mr. Boscombe here, and that man Stanley, intended to kill Ames. At least, Calvin Boscombe was to kill him, with Stanley looking on. Don Hastings saw the whole thing through the skylight. They intended to be—oh, so cool and detached and scientific, and show up the police for such bunglers when the perfect murder was committed! They had the stage all set. Only somebody beat them to it. And when that happened the two perfect murderers nearly fainted with fright and haven’t been able to talk sense yet.”
    She stood back from the door, and they saw Boscombe.
    He was bending forward near the door, restrained by Sergeant Betts’s arm, and his face wore a sly and witless look as he tried to peer into the room. It was a queer little tableau: Boscombe with his mouse-coloured hair and his sharp face and his dark-grey dressing-gown against the white panelling, the gold chain of his pince-nez dangling down from one ear as he tried to fight his way into the room past Betts. The sergeant set him back on his heels with ajar. Then, at a sign from Hadley, he shoved him forward; and Boscombe, imperturbable, came softly into the room.
    “Am I to understand,” he said, jerkily, and shook himself to settle his clothes, “that that man upstairs was a police officer?”
    “Didn’t you know it?” asked Hadley, with silky quietness. “You offered him a suit of clothes, you know. Yes, he was a police officer.”
    “Good God !” said Boscombe. He turned round and began to swab at the beads of sweat on his upper lip.
    “And I’m sure, old boy,” said Miss Handreth, studying him with an air of detached interest, “that you and Stanley would have swung for him if the business had gone through as you planned it. The perfect murder …” She turned to Hadley. The flood of words had brought a tinge of colour to her cheeks. “That’s what I meant by the funny part of it; that’s why the plan ought to have gone through, Don says. Boscombe didn’t know Ames was a policeman. And Stanley didn’t know who the victim was to be.” She began to laugh, her arms folded, and a strange beauty suddenly glowing through her face. “And you preaching on coolness to that nervous wreck upstairs, and him swilling brandy, and your hand shaking so you could hardly hold the gun—!”
    Boscombe was a trifle dazed, as though he found himself surrounded and penned in by unexpected enemies. He turned round helplessly.
    “I hardly expected,” he said, “from you, Lucia … I—you don’t understand! I only meant to give that overgrown braggart a scare, with all his talk of his own nerve …”
    “Don’t lie. Don,” she retorted, “followed every move you made, through that skylight, and a jolly lucky thing he did. He knew about the idea a month ago, when you were first talking to Stanley about ‘the psychology of murder,’ and ‘the reactions of the human brain when its owner is face to face with death,’ and all the rest of that poisonous bilge … to prove what a superman you were …”
    Hadley hammered on the table. Lucia Handreth, who was breathing hard, backed away, and Hadley glared round the circle.
    “I will have some sense out of this!” said Hadley, with an effort. “Now,” he added, after a pause and in a voice of shaky ease, “suppose we make some sort of effort to get this straight.