Is it just the liquid nitrogen? Stan worried, bending into the frigid gale. Or did the helium line break as well? The first would be a setback. The latter might mean catastrophe.

He managed to join a crowd of techs sheltering behind one of the chemosynthesis vats. Clutching flapping work coats, the others stared toward the tangle of scaffolding, where a broken pipe now spewed cutting cold. Meters beyond that impassable barrier, two figures huddled on a teetering catwalk. The shivering workers were isolated, with no visible way to escape or to reach the cutoff valve atop the towering cryogenics tanks.

Someone pointed higher, near the arched ceiling, and Stan gasped. There, dangling from a cluster of stalactites, hung Alex! He had one arm draped through a gap between two of the hanging rock-forms, just above where they fused. It looked like an awfully precarious perch.

“How’d he get up there?.”

Stan had to repeat the question over the roar of frigid, pressurized gas. A woman in a brown smock pointed to where a metal ladder lay crystallized and shattered amid the jetting frost. “He was trying to get past the jet to the cutoff valve… but the ladder buckled! Now he’s trapped!”

From his perilous position, the young physicist gestured and shouted. One of the techs, a full-blooded Maori from George Hutton’s own iwi, started scrambling for pieces of hardware. Soon he was whirling a heavy object at the end of a cable, sending it flying on an upward arc. Alex missed the tool itself, but caught the cable round his left arm. Bits of crumbling limestone rained from his shaky roost as he used his teeth and one hand to reel in a drill with a rock-bolt bit already in place.

How can he find the leverage to…