This third Shannara yarn (The Sword of Shannara, 1977; The Elfstones of Shannara, 1982, paperback only) concludes what is not so much a trilogy as a series with the same tenuous, unconvincing backdrop. Once again evil threatens to engulf the world, this time spread by hordes of pugnacious Gnomes and spectral Mord Wraiths--all of them inspired by an ancient tome of dark sorcery, the Ildatch. Several good guys are determined to locate and destroy the Ildatch, however: Allanon, last of the powerful Druids: young Brin, whose magical "wishsong" is capable of altering reality and blasting enemies (she's reluctant to use this hard-to-control ability); and her faithful brother Jair, who can produce magical illusions. The narrative does offer a few promising ideas, the odd glimmer of involvement, some exciting moments, and a reasonably well-handled plot--so Brooks fans will certainly be pleased. But the good-vs.-evil clash here remains implausibly motivated, thoroughly unfocused--with little to attract readers looking for more than stock heroics, standard menaces, and laser-beam magicking.