She laid a sculptured hand on his arm. She was silent. She was waiting. The _Dekka's_ summons brooked no delay. For this was no game of mere intrigue, but a gigantic fight instinct with the overwhelming drama of the unseen. The huge Mutant on the floor groaned and rolled to one knee. He had the strength and courage of a _Felirene_. He got up and rushed with scorn and hatred written on his features. He came with all rockets firing. Julian stood there in the battering storm and fought back. He dug his left into the flesh of the Mutant inches deep, then ripped a hook to his jaw. In the clinch that followed he could hear Narda's sobbing breath, as the Mutant's laces pounded low; he countered with secret, murderous tactics of his own. Then, he pulled the trigger on his left hand, aiming with precision at a vital spot. He let it go. He heard the Mutant crash against the floor and lay still. Julian stood for a moment with his tongue on fire, his lungs heaving like bellows with the effort. He bent down and forced himself to search the man, but there were no clues on the giant. * * * * * From above, Atalanta was like a gargantuan bottle left behind by some god in his cups. Narda at the controls brought the intra-Moon spacer spiraling down expertly to a landing behind a concealing rampart of rock. Ahead of them a black, basaltic cliff reared its jagged crags, its boulder-strewn base seemingly impassable. Nevertheless, the two masked and cloaked figures hurried their steps toward the desolate barrier. "We're probably late!" Julian observed. "We seem to be the last to arrive." He drew his dark, _Felirene_-lined cloak closer about him and led the way forward. "Small loss if we've missed the preliminaries!" Narda replied. "I wonder how much longer the _Dekka's_ going to wait? For fifty years Mutants have been appearing in our midst in small numbers--changed overnight, rendered sterile--and the scientists did nothing about it. Lately it has become a plague that threatens the Moons with extinction, and still we're fumbling in the dark! Oh, Julian!" Her voice rose in an ascending scale of grief. "Don't move!" Julian whispered harshly and froze into immobility. He'd detected motion--something that had stirred among the boulders to his right. Instinctively his fingers groped for the handle of the tiny weapon under his arm-pit. No bigger than a toy-gun, its electronic stream was devastating at close quarters. He aimed it at the spot where he had sensed movement and fired as a darker shadow catapulted out of the gloom. The spectral-blue beam of radiance from the weapon met the creature in midair and melted a jagged hole in its side; there was a fiendish scream of agony, then briefly a muffled tumult among the boulders. "What on Jupiter was it?"