In this mesmerising follow-up to Nightlights, Lorena Alvarez explores our relationship with nature and animals. On a school field trip to the river, Sandy wanders away from her classmates and discovers an empty turtle shell. Peeking through the dark hole, she suddenly finds herself within a magical new dimension. Filled with sculptures, paintings and books, the turtle's shell is a museum of the natural world. But one painting is incomplete, and the turtle needs Sandy's help to finish it...