This Fortress World by James Gunn

like the one I had taken from the Agent. This had a long, slim barrel. It slipped under his arm, inside his jacket.
    He was getting ready to leave. I watched him, not knowing what to say. Finally he turned back toward me.
    "We'd better be moving along," he said easily. "This place may not be—"
    He stiffened, and I felt a strange, unlocalized sense of alarm. A moment later, from beyond what was apparently an adjoining room, came a loud, officious knocking.
    Siller crouched. "Knock!" he whispered viciously. "Come in and get a taste of hell!"
    Slowly, casually, as if the scene just before had never happened, he straightened and turned a carefree face toward me. "On your feet," he said. He was beside the doorway leading, I presumed, to the bookshop. In that direction, at least, the knocking continued. He pressed a section of the door frame. Nothing happened.
    "Who is it?" I asked. The knocking stopped, ominously.
    Siller looked at me, apparently surprised that I was still lying on the bunk. He shrugged. "Some customer, perhaps. The shop is closed. Permanently."
    While Siller went to the draped wall opposite the doorway, I listened in silent torment to the beginning of a sound I was coming to know too well—a thin, spitting sound, muffled now by distance. Then, in the other room, a crash, a shout, and a crackling roar. The last sound was meaningless to me. Then a wave of heat radiated from the wall, and a tongue of flame licked through the doorway.
    "Come on!" Siller's voice was impatient. "Get up. Even if I could wait, the fire won't."
    I looked toward him. He was standing by the wall, holding back a drape from a rectangular, black opening. I sat up. The room wavered and spun. I forced myself slowly to my feet. The room rocked under me. Instinctively I reached out to support myself against the nearest wall. The hand jerked itself back without my volition; the wall was smoking hot.
    I clenched my teeth and concentrated on taking a step. Sweat beaded my forehead as the room steadied. There were ten steps in all. I took five of them cautiously, slowly, as if I were balancing myself on a thin wire above a gulf. On the sixth step I stumbled. The last four I made in a headlong dive. At the last moment I grabbed the edge of the doorway with both hands to keep myself from plunging through.
    "Good man," said Siller, patting my arm. "I had to make sure you were worth taking along."
    I raised my head with great effort. Siller's face was a pink blur. I forced the words out like bitter pellets. "And—if I hadn't—made it?"
    Siller's voice had a shrug in it. "I would probably have left you here."
    The flames were eating hungrily into the room behind us, but the space beyond the wall opening was dark. A slim tube in Siller's hand became a light and illuminated a corridor. I took a step. It was not so much a corridor as an unfinished space between two rough walls. Dusty, cob-webbed, it was littered with broken boards, pieces of metal and plastic, and other discarded building materials.
    Behind me, Siller slid a thick plastic door into the opening and touched a button beside the doorway. A thin line of fire ran around the edge and sputtered out.
    "Now," Siller said, chucklingly, "if they save this room—as they probably will—let them figure out how we left it."
    He draped my left arm around his shoulders and led me down the musty corridor. Even in my exhaustion, I wondered at the weight Siller's slight figure could bear without apparent effort. For the trip seemed eternal, and the light splashing ahead suggested no changes in the corridor, no possible end to the journey. Stumbling, coughing in the haze of dust raised by our feet, I made my way onward until time and distance became meaningless.
    At the end of eternity the feet stopped, and I stopped, and Siller was gone from beneath my arm. I sagged against something hard and rough, and Siller made vague, blurred motions in front of a blank wall. Then there was a doorway where the wall had