In this fourth installment of her much-loved World War I mystery series centering on the intrigue and escapades of the Reavley family, Anne Perry brings her considerable creative writing talents to this historical setting once again.

The story opens in mid-July 1917 on the Western Front. It has been three years of latrines, corpses and poison gas for Chaplain Joseph Reavley. The war has dragged on longer than anyone predicted, and Joseph has had to write too many condolence letters to surviving family members. The losses have been overwhelming. Even Cambridgeshires, his boyhood region, has lost many of their young men. And though Joseph has tended to the troops to the best of his abilities, morale is declining --- and there is even talk of mutiny.

When a respected major is killed in action, an incompetent Major Northrup fills his place. Northrup ignores the warnings of the experienced soldiers under his command and sends more men to an unnecessary end. His death follows shortly, but it's murder. When Northrup's father, an English general, demands that justice be carried out, Joseph is delegated to discover the truth and uncover the murderer.

Joseph's brother, Matthew, is also struggling with his own challenges. A major in the Secret Intelligence Service in England, Matthew is still trying to deal with his role in ending the life of the Peacemaker --- the man who engineered the death of his parents while enroute to deliver a secret document to Matthew. The document was a draft of a proposed treaty between King Edward and Kaiser Wilhelm, masterminded by the Peacemaker and a few select others to create an English/German alliance that would rule the Western world.

However, when a Junior Cabinet Minister who is being blackmailed informs Matthew of a plot that could have been organized only by the Peacemaker, Matthew is shaken by the realization that the Peacemaker is alive and has a larger network of operatives working than previously thought. Knowing that the Peacemaker will surely have another grand plan for England and Germany, Matthew sets out to uncover him again. Though he manages to survive attempts on his life, Matthew is still in grave danger.

Back on the continent, Joseph continues to investigate the murder of Major Northrup, which leads him to evidence of a "Kangaroo Court." Twelve soldiers under Northrup's command had put Northrup on trial for his incompetence and ignorance, hoping to convince the major to change. But someone killed him instead. The soldiers are arrested and held for trial. Joseph's sister, Judith, an ambulance driver on the Western front, is angst-ridden over the potential court martial and execution. She aids in the escape for all but one of the 12 indicted soldiers.

As Joseph prepares to find the escaped men and bring them home, he uncovers who killed the major. The court-martial trial is scheduled to proceed in spite of the circumstances of the war and what has been discovered. The headquarters in London request that Joseph represent the accused men. Even though an army legal officer reminds Joseph that he knows "the trenches, the army, the reality of life and death and loyalty and what it means to be part of regiment," Joseph still doubts his legal abilities. But he begins to discover a way to defend the soldiers and comes to realize that it's all about having faith and making sure it endures regardless of place or time.

Anne Perry's ability to plot an intriguing mystery series is never more adept than it is here. Her flair as a writer brings to life the story of the Reavley family as every member faces the catastrophes that World War I brings to their lives. She delves deep into the hearts of her characters and their anguish as they struggle with good and evil, and the atrocities of war.