Murder for Two by George Harmon Coxe

wooden door with the polished brass knocker, tried it, and found it locked. He took some keys from his pocket, and though he scarcely made a sound he had the door open in less than a minute.
    Inside a light burned and they went into a tiny vestibule, climbed three steps, and opened a second door which was unlocked. That put them in a small, high-ceilinged hall that was warm and musty with age. Two doors opened from opposite sides of this, and directly ahead was a thinly carpeted stairway mounting stiffly along the left wall.
    They climbed the three flights silently, Blondie ahead, Casey in the middle. He had stopped trying to guess the answer to this one. It was obvious that they had seen the note Karen Harding had left, getting the address the same way he had; but if they had wanted something from her why had they waited for him?
    Well, that part didn’t matter. He was here and now he was glad of it; for it was better that he should be with her now than let her face these two alone. Take care of her, MacGrath had said that morning. Was that a laugh?
    Blondie stopped just short of the third-floor landing. “You get us in, friend. Just tell her who you are.”
    â€œSuppose she doesn’t answer?” Casey said.
    â€œIf she’s got a doorbell, she’ll answer,” Blondie said, “or else she’ll get awfully damn sick of hearing it.”
    He went on to the landing and Casey followed. When he reached it he tried to get his back to the wall but Harry jabbed with the gun and stayed behind and that was the end of the only idea Casey could think of. Harry might not shoot but he would certainly slug with that gun the first move Casey made, and if he was laid out here in the hall he couldn’t be much help to Karen Harding. Of course he could yell a warning, but that might scare Harry into pulling the trigger a few times.
    He watched the man press the button, the feel of the gun on his spine. The little hall was hot and humid.
    Presently the faint sound of movement filtered through the door and Karen Harding’s voice said, “Yes? Who is it?”
    Harry punched with his gun. Casey said, “Casey.”
    The latch clicked back. “Stand still, pal,” Harry said. The door began to open and Blondie moved in, widening the crack with his shoulder and pushing the gun ahead of him.
    â€œIt’s okay, sis,” he said. “Just don’t make any noise.”
    Casey heard the girl’s startled, “Oh,” and moved up. She was backing into the living-room and over Blondie’s shoulder he could see she was wearing a green flannel robe, one hand holding it tightly at the throat.
    â€œHi,” Casey said, trying to make his tone reassuring. “These guys sort of had me over a barrel.”
    Harry closed the door and stayed there. Blondie waved the gun. “We were coming without Casey,” he said to Karen Harding. “We figured we could imitate his voice, only”—he looked at Casey and showed his crooked teeth—“just as we’re leaving the Express some guy drives him up and out he gets. So we stuck around and brought him too. Where’s the film?”
    Karen Harding looked at Casey. Pajama legs showed beneath the robe and she had her blond hair shoved back of her ears and her face was grave and shiny with cold cream.
    Casey tried to pretend that everything was all right. “I told these guys they were nuts,” he said.
    â€œWhat film?” Karen Harding said.
    â€œThe one that goes with this,” Blondie said and brought out a print that had been folded once.
    Karen Harding glanced at it and a tightness came about her cheekbones. She put up her chin and looked right at Blondie. But there was something besides defiance in her gaze and Casey saw it. Suddenly that prickly sensation crawled along his scalp and he was scared. What the hell had she done now? What could she know about any prints?
    â€œI don’t know what you