The Nightblood Prince is the second installment in the Xian series, continuing the story of Ruying, a young woman gifted with the power of Death. Following the events of the first book, Ruying must navigate her complicated alliance with the Roman prince Antony while dealing with the escalating conflict between her magical homeland and the technologically advanced invaders. As she becomes further entrenched in the resistance, she is forced to confront the moral cost of her abilities and the true nature of the empire she serves.