On the way to see a client, Maisie Dobbs witnesses a man committing suicide on a busy London street. The following day, the Prime Minister's office receives a letter threatening a massive loss of life if certain demands are not met - and the writer mentions Maisie by name. Tapped by Scotland Yard's elite Special Branch to be a special adviser on the case, Maisie is soon involved in a race against time to find a man who proves he has the knowledge...