London, 1921. The Great War has recently ended and tensions in England are high. Now, prominent Cabinet minister Lord Amersham has been shot dead outside his Regent's Park home and the signs point to a professional hit. Charged with solving one of the most sensitive and high-profile cases Scotland Yard has ever faced, DCI Paul Stark is under pressure to get the job done quickly. Winston Churchill, Secretary of State for the Colonies, is convinced the Bolsheviks are responsible. Stark's contemporaries at Special Branch suspect a connection to Government talks about Irish Home Rule. And others believe the motive could be connected to Lord Amersham's rather scandalous private life . . . When a second crime occurs - another murder committed by an expert marksman at close range - the case takes a terrifying turn and puts Stark right in the middle of an international crisis.