More than a few too many characters, subplots, and themes muffle the impact of this grandiose historical picaresque by the Mexican author of the previously translated and essentially similar 1492 (1991). Aridjis's narrative is divided into 27 ``visions'' seen, and relayed to the reader, by Alfonso de LÇon, a monk whose dedication to his vocation as an illuminator of manuscripts does not protect him from yielding frequently to carnal desires or from the threat of a bloody reunion with his malevolent twin brother, Abd Allah of Cordova, a powerful warrior member of the Saracen armies whom Alfonso and his brethren devoutly believe ``will annihilate all Christendom before the year 1000 comes to an end.'' The novel begins in a confusing welter of unrelated scenes, then settles for a time into a chronological account of the twins' birth (to a Moorish Caliph's concubine), their upbringing and education, and the separate paths their warring temperaments set them on. Then we're swiftly cast back to a kaleidoscopic landscape delineated with apocalyptic imagery and numbingly explicit descriptions of sexual acts and physical violence, and populated by assorted minstrels, pilgrims, hermaphrodites, and such laboriously fabricated grotesques as Isidoro, the Messiah of the Poor, a kind of Marxist Lord of Misrule reputed to possess ``a celestial letter signed by the Lord Jesus, which...authenticated him as the true Son of God.'' We feel the book straining to impress its readers (the addition of a nine-page Bibliography seems, shall we say, a trifle pretentious?). Eventually, though, the conflict between the brothers resurfaces, then climaxes in battle, finally determining whether Alfonso indeed is ``the Lord of the Last Days'' who will bind up the Evil One, thus preserving the Christian faith for another thousand years. The seed of a powerful fiction here becomes drenched early on by melodramatic fustian, and never grows into anything remotely resembling a coherent novel.