May, 1915. Alfie and his fisherman father find a girl on an uninhabited island in the Scillies - injured, thirsty, lost. and with absolutely no memory of who she is, or how she came to be there. She can say only one word: Lucy. Where has she come from? Is she a mermaid, the victim of a German U-boat, or even - as some islanders suggest - a German s