For eleven-year-old Flavia de Luce, a visit to a Gypsy fortune-teller is just a bit of fun - until the old woman claims to see a vision of Flavia's mother, who died when Flavia was a baby. When the Gypsy is brutally attacked, Flavia wonders if her appearance in the village has stirred up memories of a tragic event from the past.

Flavia starts down a dark and twisting road to discover the truth - but when a corpse is found in the grounds of Buckshaw, the de Luce family seat, it seems as if the heart of the mystery is disturbingly close to home.