As darkness falls on 10 May, 1975, a little boy stands alone on the steps of an amusement park. The park is about to close and everyone is leaving, except this child. He continues to stand there, not daring to move. He was been told to stay right where he is.Only no one is coming back for him. Why has he been abandoned, with only the briefest of notes to whoever finds him? And what connection do the events of this day have to the death of Gerda Persson thirty years later – a woman who leaves few clues to her life, apart from a freezer full of books? Shadow is an unputdownable story of dark secrets, murder and the depths to which the human mind will sink in order to protect its own . . .