Mercury Shell, Venus Shell, Earth, Mars, Asteroid, Jupiter, Saturn. Each shell concentric, studded with artificial planets, each planet embedded in its shell, spinning like a ball-bearing. The whole Zeus-created in the service of Man but now beyond his control. Now mathematics and space physics, converging, suggested another shell, its existence hidden from Man. A shell of utter darkness, cold and silence where only extreme mutants could survive. To find that shell, the three were journeying Maq Ancor, Master Assassin, Magician Cherry and Sine Anura, Mistress of the Erotic. Together, daring the all-seeing, all-sensing hostility of Zeus.
Colin Derek Ivor Kapp was a popular UK science fiction author, but one who never became a success in the USA. He was active, though not prolific, as an author in the 1960s through to the 1980s.
He is best known for his "Unorthodox Engineers" stories, which recount an eccentric group of engineers, who accomplish impossible feats of engineering against all odds.