The Travels of Audrey Green: The Audrey Green Chronicles

The Travels of Audrey Green finally addresses the drowning of Antony Green, briefly mentioned in the other two books. Antony was six years old and waded out into the Channel, claiming he had found an underwater train before drifting away. It's 1953 in Burnby, England, and Alison Falliher, wife of a police inspector, becomes obsessed with the drowning. In her post box, she receives an unmarked letter of instructions: 'Go in secret to St. Peter's Church; the boy's not drowned.' There, she meets a man in a 'borrowed' body...