Three separate plots intertwine to conclude the fantasy trilogy. Novice Singer Kyarra discovers her mother living as a brain-wiped prisoner of the Echorium, only to be captured by pirates hired to convey the pair to her unknown father. Across the sea, a flock of “quetzals” (birdlike “Half Creatures”) worship the sinister Starmaker; but a captive Singer frees their leader Night Plume from his enchantments, begging him to enlist the Echorium’s aid. Revealed as both Kyarra’s father and the villainous priest Frazhin, the Starmaker’s crimes inspire the various human tribes to join the Singers in an assault upon his volcanic lair, as he schemes to rewrite history by corrupting the quetzal “Memoryplace.” Roberts weaves her narrative skillfully, and makes a commendable effort to tie up loose ends for nearly every character in the series. But the endearing Half Creatures excepted, her characters remain abusive, ineffective, or just plain unpleasant. A dizzying array of magics, burdened with an oddly pedestrian nomenclature, undermines the sense of wonder, while the anticlimactic resolution is likely to leave readers vaguely dissatisfied. Purchase where the earlier titles are popular. (Fantasy. 10-14)