Otherland, the quartet of which Mountain of Black Glass is the powerful third part, combines some terrifying speculation on the future of virtual reality with adventures no less terrifying because they are technologized dreaming. An epidemic of comatose children has led Renie and her San friend !Xabbu into the net and to a series of dream worlds created as palaces by the corrupt aspiring immortals, the Grail Brotherhood. Two of those children, Orlando and Fredericks, have become adventurers in their own right, while their parents' lawyer Ramsey follows real-world money and lesbian cop Calliope tracks a serial killer with serious ambitions to become an angry god. In this volume, adventures take place in a mythic ancient Egypt and a rambling Gormenghastlike house before all the virtual adventurers meet where they were always destined to, before the walls of Troy.