Mountain of Black Glass is the third volume of Tad Williams's highly acclaimed four-book series, Otherland. A truly unique reading experience combining elements of science fiction, fantasy, and techno-thriller, it is a rich epic tale in which virtual reality could prove the key to a whole new universe of possibilities for the entire human race - or become the exclusive domain of the rich and the ruthless as they seek a technological pathway to immortality.

A group of adventurers searching for a cure for comatose children find themselves trapped in a sequence of virtual worlds, the only opponents of a conspiracy of the rich to live forever in a dream. Now, they are forced to make an uneasy alliance with their only surviving former enemy against his treacherous sidekick Johnny Wulgaru, a serial killer with a chance to play God forever. Few science fiction sagas have achieved the level of critical acclaim - and best-selling popularity - as Tad Williams's Otherland novels.

Surrounded by secrecy, it is home to the wildest dreams and darkest nightmares. Incredible amounts of money have been lavished on it. The best minds of two generations have labored to build it. And somehow, bit by bit, it is claiming the Earth's most valuable resource - its children.

Golan Trevize, former councilman of the First Foundation, has chosen the future, and it is Gaia. A superorganism, Gaia is a holistic planet with a common consciousness so intensely united that every dewdrop, every pebble, every being, can speak for all - and feel for all. It is a realm in which privacy is not only undesirable, it is incomprehensible. But is it the right choice for the destiny of mankind? While Trevize feels it is, that is not enough. He must know.  

More than 3,000 years have passed since the first events recorded in Dune. Only one link survives with those tumultuous times: the grotesque figure of Leto Atreides, son of the prophet Paul Muad'Dib, and now the virtually immortal God Emperor of Dune. He alone understands the future, and he knows with a terrible certainty that the evolution of his race is at an end unless he can breed new qualities into his species.