[1][2] As in the other two books, the setting is the post-apocalyptic empire of Toromon, confined by a surrounding "Barrier" of highly-radioactive land, and inhabited by mutant/evolved "forest people" (some of whom are telepaths) and devolved "neanderthals", as well as normal humans.

However, it turns out that the matter transporter or teleportation system has never worked, and the war is a hoax.

The soldiers are wired into a computer prior to their "teleportation" experience but remain in their coffins.

However, Toromon does have a real enemy of sorts, on another plane of existence, and at the end of the book there is a cosmic conflict which leads to this entity being prevented from conducting further malicious experiments on Toromon.

The stories of the Fall of the Towers trilogy were originally set in the same post-holocaust Earth as Delany's earlier The Jewels of Aptor; however, linking references were removed in later revised editions.