Maddie McGlade, a former nanny now in her nineties, receives a letter from the last of her charges and realizes that the time has come to unburden herself of a secret she has kept for over seventy years: what really happened on the last day in the life of Charlotte Ormond, the four-year-old only daughter of the big house where Maddie was employed as a young woman. It is to Charlotte's would-be niece, Anna -pregnant with her first- that Maddie will tell her story as she nears the end of her life in a lonely nursing home in Northern Ireland.