This book simultaneously provided a thrilling adventure and a continuation of Priest's deep characterization skills. The main plot of the novel does tie back into the nightmare that Seattle has become, but first provides a deeper view of the Civil War that is still raging in the East than what is provided in Clementine. Once the action moves to the rails, the novel becomes a very tense read, and I read the last third in one sitting. The action stays well paced while interspersed with revelations about the characters and the greater world of the books. 
 While Priest is not shy about detailing the horrors of the battlefield and its human repercussions, this story shines through the strongest as the tale of people who will do what they need to do. This determination and steadfastness shows up in the major character (whose eyes we see the action through) and through several of the supporting characters. They don't shrink from challenges or the costs to be incurred. Instead they stand firm, assess the situation, and then determine the path forward. Even Mercy's loss early in the novel doesn't cripple her. Instead she takes time to regain her bearings and then carries on. The humanity of each character comes through very clearly. Compassion, ethics, and practicality co-mingle within all of the important roles in the novel, including a villain who commits the tragic mistake of seeking to do great good while causing great harm instead. 
 This is an excellent book that moved the next two novels in the series to the top of my to-buy list.