At 12, Xandra (short for Alexandra) is prickly and at odds with her distracted, emotionally distant parents and her accomplished siblings. She takes solace in imagining enchanted worlds and in privately caring for orphaned animals (a skunk, an owl, and other wild creatures) in a corner of her basement. The gift of a white feather from a mysterious bird she saves from hunters becomes for Xandra a strangely compelling key to a surrounding, separate reality. She immediately senses the feather’s intrinsic power and seeks out her classmate, Beatrice, to tell her more. Wielding the key with its possibilities of insight and great danger brings Xandra into contact with terrifying shadowy creatures that threaten and bite, reflections of her own ambiguous feelings, and Xandra seeks both comfort and salvation by reconnecting with her siblings. Snyder tidily braids up the ends (friendship, family, loneliness, the occult) even as her examination of resonance between inner and outer life evokes a clear sense of menace in Xandra’s experiences with the unseen. (Fiction. 10-14)