The Austins, well-met once, have become increasingly cloying in succeeding books, and Miss L'Engle's philosophic concerns, which gave urgency to A Wrinkle in Time, have begun to seem pretentious, their expression sententious. The Young Unicorns is a kind of aggiornamento of the Austin series and The Arm of the Starfish--via cross-references and a congeries of characters--and Wrinkle. . . the latter because seven-year-old Rob Austin speaks with the same precocious wisdom as Charles Wallace and, in the clinch, withstands evil with the same indomitable innocence: the roles are interchangeable. Coequal with the Austins, who've moved to Manhattan, are two youngsters whom they've absorbed, twelve-year-old Emily, a piano prodigy mysteriously blinded, and Dave, an older misfit who used to run with the Alphabets gang. Dad seems disturbed about his work on a microray instrument; the children are frightened by the materialization of a genie when they rub an antique lamp, by stalking Alphabets everywhere. The plot is labyrinthine, and much of the exposition is borne by the dialogue. It seems that Dad's boss, Dr. Hyde, is plotting with the Bishop of the focal-point Cathedral to take over the city by manipulating the minds of the Alphabets with the microray and he needs a key equation from Dad. . . only it isn't the Bishop, it's his actor-brother who impersonated him after his death. Miss L'Engle envelops these melodramatics in church music and theological speculations; she also writes with an insinuating slickness: the insupportable is readable.