In 1944, Dart and Tamar, code names for two undercover operatives for Britain’s Special Operations Executive, parachute into Holland to reorganize the Dutch resistance movement. In 1955, a 15-year-old British girl named Tamar receives a box from her grandfather who has committed suicide. In it are clues to her grandfather’s past and her own identity, but she must go on a journey to make sense of the clues. In Peet’s Carnegie Medal–winning work, he tells the interwoven stories of Tamar the spy and Tamar the teenager in beautifully visualized episodes. Meticulously crafted scenes develop this long, complex and elegant work that is both a historical novel and a reflection on history—how a young girl’s life has been shaped by a past she never knew. Readers will be torn: They’ll want to slow down and savor the gorgeously detailed prose, but speed up to find out what happens next. Simply superb. (notes, acknowledgments) (Fiction. YA)