Who is killing off members of the Falconer family and why? Such is the challenge confronting highly skilled, extraordinarily intuitive Mary Wandwalker when she finds herself single, sixty and jobless. Long ago as an Oxford student with an unplanned pregnancy, Mary knew the Falconers as the family who refused to help when her fiancé, David Falconer died in a car crash. Now the baby boy she gave up for adoption is a policeman, George Jones, and he wants to meet her. Can Mary bring herself to confront her past? She must, for lost in her memory is a clue that could save her son's life.

Back in 1979, Mary wrote to the Falconers and was rejected. Now forty years later, key phrases from her letter appear in the faked suicide note of Perdita Falconer. Neither Perdita nor her killer had access to Mary's document. Too exact for coincidence, the link is the pseudonym of the drug dealer who supplied her fatal dose. He or she is known as "the Kestrel."

When Mary was romanced by David Falconer in the 1970s, "the Kestrel" was codename for a Russian spy entertained at Falconer House. Could the resurrection of the nom de plume be connected to Viktor Solokov, the Russian oligarch renting the Falconer estate with his beautiful wife, Anna? For the Falconers have dark secrets, some centuries old.

When George Jones's wife Caroline begs Mary to save her husband from treacherous Anna, and the murderous talons of the Kestrel, Mary must act.