Thirty years ago, on Mother's Day, Mary Byrd Thornton's nine-year-old stepbrother was murdered. His killer was never found. At the time, Mary Byrd had been fifteen: in love and caught up in the excitement of the Sixties, but when Stevie died, her family and her life fell apart.

For years she has struggled with the knowledge that the murderer is still out there, as well as her own nagging guilt over Stevie's death. Yet she has built a life for herself in Mississippi: she has married a Southern gentleman and has two children she adores. With her ramshackle house, her teeming garden and her menagerie of animals, she is immersed in a comfortable, if somewhat eccentric and occasionally restless day-to-day existence.

When a journalist chances upon the mystery of Stevie's death and begins to dig into it, Mary Byrd suddenly finds herself on a reluctant journey back to her childhood home in Virginia. Along the way she encounters help from unexpected quarters and finds herself confronting not only her family's story but the stories of many others – both the living and the dead.