One of Newbery Honor author Avi's most popular middle-grade mysteries is available in paper once again.  The mystery revolves around a rare edition of <i>The Wizard of Oz</i> missing from the local library. When Becky is accused of stealing it, she and her twin brother Toby set out to catch the <i>real</i> thief and prove her innocence. Clues cleverly hidden in four other books lead to a hidden treasure--and a gripping adventure.