Out of Oz (William Morrow, $26.99), the eagerly awaited conclusion to the Wicked Years, has arrived. A battle for the future of the Thropp dynasty is under way, as Elphaba and Nessarose’s younger brother, Shell, the Emperor Apostle, increases his influence; and the political power struggle continues in the Emerald City and spreads into a civil war, as the witch Mombey, who changes her heads as others change hats, challenges his ambitions. A former acting ruler of Oz, Glinda is placed under house arrest; the Lion, Candle, and Liir are on the run to protect the otherworldly Grimmerie. As always, the future depends on children: Rain, a broom girl from Glinda’s entourage; a young street urchin named Tip; and the legendary Dorothy.  Gregory Maguire has an amazing knack for honoring the L. Frank Baum tradition while integrating new characters who both complicate and deepen that magical reality.