The second installment of The Ferren Trilogy is set in a post-apocalyptic world where humanity’s fate hangs in the balance. Ferren, a 15-year-old “Residual,” or human being, from the “People” tribe, and Miriael, an angel barred from returning to heaven, may be the only hope for the future of humanity. Together, they travel to find the remaining fractured tribes, including the Sea-folk and Nesters, in an effort to recruit members for their newly formed Residual Alliance to fight against their common enemy, the Humen—mechanical war machines led by the sinister Doctor Saniette, an 80-foot-tall machine in human form. This fight is made especially challenging because the tribes believe the Humen are their allies, forcing Ferren to face the painstaking task of educating each tribe about the Humen’s true nature. Along the way, Miriael receives a tempting offer from a fellow angel—a chance to reclaim her place in heaven. The decision she makes will not only determine her fate, but also the fate of Ferren, the ongoing war, and the world. Harland paints a vivid and immersive backdrop, delving into a futuristic landscape fraught with political intrigue and moral ambiguity. The thought-provoking exploration of power dynamics and the consequences of humanity’s hubris adds depth to the story. The novel brims with creative details, like a “thunderous, clanking mechanical monster” and swarms of spiraling, malevolent seagulls, but the writing, however, occasionally lacks polish. Still, the storytelling is solid, offering readers an engaging continuation of The Ferren Trilogy.