Wolkstein (Step By Step, 1994, etc.) writes, in diary form, the story of Esther, the Jewish orphan who became queen of Persia and kept her identity a secret until her people were in danger of destruction at the hands of the prime minister, Haman. At great risk, she prevailed upon King Ahasuerus (Xerxes I) to modify the death decree to allow the Jews to defend themselves against any who attacked them. Their survival and Haman's downfall are celebrated in the festival of Purim. The diary format confers immediacy; readers share the loneliness, fears, and determination of this legendary heroine of nearly 25 centuries ago. Wijngaard has illustrated sumptuous court settings before, in Selina Hastings's Sir Gawain and the Loathly Lady (1985). As in that work, his jewel- toned gouache paintings are a virtual museum of period dress, decoration, and architecture; a six-pointed star motif is worked into many of the geometric backgrounds. Elegant and enlightening. (pronunciation guide, notes) (Picture book. 7-11)