“And you did just that, Nora. The door was open for Ludlow at two-twenty. Ralph was there waiting for his picture, but you weren’t.”
“Where was I, mastermind?” she asked scathingly.
“You were in Ralph’s kitchen going out his back door onto the fire escape with his back-door key, which is just a common one that opens most ordinary doors. I tried my back-door key on his this afternoon and it fits, all right. You worked fast to get out of a hell of a spot after you stabbed him. You knew the photographer was due in that open doorway any moment. I imagine you ducked in the kitchen with your clothes in your arms about the time Ludlow walked in. Or did Ralph wake up before you were fully undressed, threaten to throw you out, and got you so angry you grabbed up the paper knife and let him have it, before you realized you were trapped there?”
“You’re telling it,” she said, feigning indifference, but her voice was unsteady.
“That’s right, I am,” he agreed pleasantly. “Anyhow, you did come out on the fire escape, bringing the backdoor key to two-sixteen with you, and down one flight to my landing. By that time, you’d had a moment to think. Ralph was dead, and the detective and photographer would place you in his room at the right time. If you could get into the apartment below, pretend you believed it was Ralph’s and that you had been given the wrong key by mistake; well, it was a crazy chance, but the only one you saw. And you took it, babe, with the aplomb of a seasoned murderess, may I say? I don’t know how much practice you’d had, but—”
“You actually sound serious,” Nora broke in, bewildered and frightened. “How can you possibly believe all that nonsense? I had no way of getting into Ralph’s room. That key doesn’t fit his door. You and the chief tried it last night.”
“No,” said Shayne grimly. “That was a big break for you. The merest chance, but it almost put you in the clear. The police had jammed the lock on Ralph’s door when they broke in, and we brought his key down here to try it on my door. It didn’t fit, of course. But we didn’t try this key on my door. You said you’d come in the front door and we assumed you had, and it didn’t occur to us to test it.
“But after it was all over and you had Ted Granger conveniently dead and framed for the job, you realized that I still had the key. ‘One of these days,’ you must have thought, ‘he’ll absent-mindedly try to open his door with that key I left behind, and it won’t open’
“You knew that would be the payoff. I’d immediately know your entire story had been a lie. But if you could get hold of this key, and get rid of it before I happened to try it on my door, you’d be clear. And you tried, honey,” he went on, his voice suddenly sympathetic. “God knows you tried. That’s why I expected your call tonight. I knew you’d call.”
Nora Carrol had been leaning back listlessly as he spoke, nervously toying with the suède purse in her lap. Her hand dived inside as he ended, and came out with a tiny.25 automatic. She sat up with teeth bared and her finger tight on the trigger.
“All right, you smart bastard,” she grated. “Once that key is gone you’ll never prove a thing. Give it to me.” Shayne shrugged and tossed it into her lap. “You can have it. I didn’t mention that you forgot something else. Your fingerprints are on Ralph’s back doorknob and on mine. If you had wiped those off—”
“I did wipe them off. You’re lying—”
Shayne jerked his right foot, that had the toe of his shoe under the edge of her chair, just as she realized what she had said. She pulled the trigger of her automatic, and the small bullet went over his head into the ceiling. He had her in his arms, with one hand clamped over the gun, while his other reached for the telephone to call the police to take her away.