Miller's episodic, ironic, deeply moving, and only previous novel, A Canticle for Leibowitz (1959), remains one of science fiction's enduring masterpieces. This quasi-sequel--the chronologies can't be reconciled--was, according to the publisher, ``85% complete'' upon the author's death in 1996; short-story expert Bisson (Pirates of the Universe, 1996, etc.) completed it. The Abbey of San Leibowitz, located in America's Southwest, has survived into the 32nd century, but various empires, hostile tribes, and ecclesiastical power struggles threaten to destroy the political stability of the region, and the Papacy along with it. Among the characters who will play crucial roles in this conflict- -which seems to invite allegorical interpretations--are: the disgraced and reluctant monk of Leibowitz Abbey, Blacktooth St. George; Father e'Laiden, a priest under interdict; Holy (Little Bear) Madness, a wild but aristocratic Nomad; seaman, warrior, and executioner Wooshin; the Red Deacon, Cardinal Brownpony; ídrea, a beautiful ``gennie'' (mutant) and nun, with whom Blacktooth becomes emotionally and physically involved; and Benjamin, the mysterious old Jew of the Mesa of Last Resort, who may be both the Wandering Jew and Saint Leibowitz himself. Dense, meandering, with a bewildering cast of thousands, and not very enlightening either: a book that almost every aficionado of Miller's masterpiece will want to attempt, but very few will finish.