I shrugged. "Maybe he had a high resistance to Mickey Finns.

Maybe he saw too much, or knew too much. Or both."

"But—but now they know you've seen too much and know too much." I wished she wouldn't look at me when she was talking, these eyes would have made even the Rev. Smallwood forget himself in the middle of his most thundering denunciations—not that I could imagine Mr Smallwood going in for thundering denunciations very much.

"A disquieting thought," I admitted, "and one that has occurred to me several times during the past half-hour. About five hundred times, I would say."

"Oh, stop it! You're probably as scared as I am." She shivered. "Let's get out of here, please. It's—it's ghastly, it's horrible. What—what was that?" Her voice finished on a sharp high note.

"What was what?" I tried to speak calmly, but that didn't stop me from glancing around nervously. Maybe she was right, maybe I was as scared as she was.

"A noise outside." Her voice was a whisper and her fingers were digging deep into the fur of my parka. "Like someone tapping the wing or the fuselage."

"Nonsense." My voice was rough, but I was on razor-edge. "You're beginning to—"

I stopped in mid-sentence. This time I could have sworn I had heard something, and it was plain that Margaret Ross had too. She twisted her head over her shoulder, looking in the direction of the noise, then slowly turned back to me, her face tense, her eyes wide and staring.

I pushed her hands away, reached for gun and torch, jumped up and started running. In the control cabin I checked abruptly -God, what a fool I'd been to leave that searchlight burning and lined up on the windscreens, blinding me with its glare, making me a perfect target for anyone crouching outside with a gun in hand—but the hesitation was momentary only. It was then or never—I could be trapped in there all night, or until the searchlight battery died. I dived head first through the windscreen, caught a pillar at the very last moment and was lying flat on the ground below in less time than I would have believed possible.

I waited five seconds, just listening, but all I could hear was the moan of the wind, the hiss of the ice spicules rustling along over the frozen snow—I'd never before heard that hissing so plainly, but then I'd never before lain with my uncovered ear on the ice-cap itself—and the thudding of my heart. And then I was on my feet, the probing torch cutting a bright swathe in the darkness before me as I ran round the plane, slipping and stumbling in my haste. Twice I made the circuit, the second time in the opposite direction, but there was no one there at all.

I stopped before the control cabin and called softly to Margaret Ross. She appeared at the window, and I said: "It's all right, there's no one here. We've both been imagining things. Come on down." I reached up my hands, caught her and lowered her to the ground.

"Why did you leave me up there, why did you leave me up there?" The words came rushing out, tumbling frantically one over the other, the anger drowned in the terror. "It was—it was horrible! The dead man. . . . Why did you leave me?"

"I'm sorry." There was a time and a place for comment on feminine injustice, unreasonableness and downright illogicality, but this wasn't it. In the way of grief and heartbreak, shock and ill-treatment, she had already had far more than she could stand. "I'm sorry," I repeated. "I shouldn't have done it. I just didn't stop to think."

She was trembling violently, so I put my arms round her and held her tightly until she had calmed down, took the searchlight and battery in one hand and her hand in my other and we walked back to the cabin together.