The #1 bestselling chapter book series of all time celebrates 25 years with new covers and a new, easy-to-use numbering system! Jack and Annie head to 18th-century Austria, where they must find and help a musician by the name of Mozart. Decked out in the craziest outfits they've ever worn--including a wig for Jack and a giant hoopskirt for Annie!--the two siblings search an entire palace to no avail. Their hunt is further hampered by the appearance...