This exciting novel of mysterious disappearances and subterranean terrors pits nuclear experts against a horror even they could not imagine. A secret: Jack Whittaker, master caver, has found an enormous cavern to rival famous Carlsbad Caverns, a place of pristine darkness, astonishing beauty and unpredictable peril. Whittaker needs to keep the cavern a secret until he can get the rights to develop it. But his ex-wife, scientist Cassandra Roberts, has another idea for the cavern, thanks to an ancient footprint found in its depths, near an emerald-like pool of water that has been undisturbed for millenniaor has it? Another secret: In another cavern, this one man-made, patiently scoured from a 2,000-foot-deep salt deposit to house radioactive nuclear waste, government employees have started to disappear. Are these mysterious vanishings a conspiracy? Enter T. L. Smith, chief of security for the Department of Energy, a man given to lies and subterfuge and, whenever needed, violence. Yet another secret: Here under the arid reaches of the New Mexican desert, evolution has produced something marvellous, something unknown to the world, something that should have disappeared with the end of the last Ice Age, a force so dangerous that once all the secrets in Carlsbad are revealed, and all the depths plumbed, more lives and even the great works of man and of nature are at risk.