After the events of the Fourth Trial, Martial soldiers hunt the two fugitives as they flee the city of Serra and undertake a perilous journey through the heart of the Empire. Laia is determined to break into Kauf - the Empire's most secure and dangerous prison - to save her brother, who is the key to the Scholars' survival. And Elias is determined to help Laia succeed, even if it means giving up his last chance at freedom. But dark forces, human...