Addie and Meryl are sisters, princesses in the kingdom of Bamarre, who love each other dearly and could not be more different. The older sister Meryl is brave and assertive, practices swordplay, and longs to go on adventures and fight monsters. Her younger sister Addie is timid and shy, scared of monsters and spiders, and prefers to stay home with her needlework. But when Meryl falls sick with the gray death, a fatal magical illness, Addie overcomes her terror and leaves the castle to search for the fabled cure. Along the way she must face everything she's most afraid of, including the prospect of losing her sister forever. This is a wonderful middle grade book, very inventive and whimsical in the same vein as Howl's Moving Castle and The Princess Bride. Reading it made me want to write a short fantasy story in which characters can fly and dragons can speak.