"What's the matter, Captain?" Torio's suave ironic voice was demanding. "Do you smell it already? You're so silent."

William Wilson, with Nina, was alone on guard in the adjacent chart room. He gave a sudden startled cry. "Come quick! Something's the matter with me."

Poisonous gas here! We realized it abruptly; gas pouring in through the ventilators from below.

"Close those vents!" Mackensie gasped. "Poisoned air—" His hand was clutching at his throat. With his thick neck, full-blooded body, he felt it worse than any of us. His face was purpling; his eyes abruptly bulging. In that second he staggered and fell, ripping the receiver connection out as he went down, where still the ironic voice of Torio was jibing at us.

The rest of us sprang to the grid vents. There was no way of shutting the poisoned air off! The hinges of the multiple little visors were melted away!

"That—that damned Dr. Frye," Polter gasped. "He was up here a while ago. I wondered—"

A scream from Nina, mingled with a sizzling flash in the other room, transfixed us. With all the weird scene swaying before me, I dashed through the oval. Young Wilson was lying sprawling, dead from a bolt, with his head and shoulders on the window ledge. Nina was crouching in a corner, gasping, staring in terror. I started toward her. My ears were roaring as though with a thousand Niagaras. A titan hand seemed compressing my chest with a band of steel as I gasped for breath.

"Nina—Nina—" My own voice, so futile, sounded far away. Then I heard the steel shutter of the chart room window snap up to the top. Into the opening, a man came climbing. Mokk, with a patch of chemical fabric binding his nose and mouth like a mask. My gun sizzled at him, but the stab went wild as I staggered. Then he came leaping at me.

From the turret I was aware of other shots; a scream of agony from Polter as he was struck; thudding blows as the visor pane was crashed. And then a scream from little Green. The end! On the chart room floor grid I found myself wildly grappling the hulking Martian. My gun had clattered away as his three hundred-pound weight crashed me down. Dimly I realized that this sudden wild attack upon us was because the bandits, for their own sakes, had no desire to have any great amount of the poisoned air circulating about the little ship.

"You damned little Earth-fool," Mokk was growling. "Don't you see I'd rather not kill you?"