One summer night, two men break into an isolated manor house and kill Lady Anne Robinson. Her son, Thomas, convinces the police that his father's beautiful personal assistant sent the killers, but Thomas is known for his overactive imagination, and he has reasons to lie.

Thomas's father, Sir Peter Robinson, the British minister of defense, refuses to believe his son. Instead, he marries his assistant, Greta Grahame, and will be giving evidence for the defense at her trial. He will be the final witness.

Author Simon Tolkien successfully combines legal suspense and psychological tension in this sharply etched portrait of four people whose lives are changed by a murder. Alternating between the trial in London's Central Criminal Court and private moments among the characters, Tolkien expertly describes the art of the trial, the clash between Britain's social classes, and, most notably, the complexity of family relations.

Who is telling the truth - the new wife or the bereaved son? What will Sir Peter tell the court? With tantalizing ambiguity, Tolkien keeps readers guessing about the true motivations of these characters until the final witness.