As two houses vie for power in a world under siege by fallen angels, a rebellious young soldier hopes to escape a brutal caste system in the city of Vega.
In light of recent revelations Alex pressures Claire to leave the city, and her father moves to keep them apart by reassigning him. Alex's secret puts him in danger from a sleeper threat inside Vega, and Gabriel brings Michael a warning about the coming conflict.
Alex's plans to leave behind Vega and his responsibilities as the Chosen One are thwarted when Michael catches up with him and they find themselves in a fight against Gabriel's forces. Claire makes a personal sacrifice for the city's people.
After Alex is arrested upon his return to Vega, a powerful Senator takes the city hostage and demands to meet the Chosen One. Elsewhere, Michael's sister Uriel summons him to a meeting of the archangels.
As Alex begins his training with Michael, Claire attempts to protect her father from David Whele's ambitions. When General Riesen's paramour makes an unauthorized excursion into the city, Alex attempts to track her down.
Alex takes on the seemingly impossible task of exorcising an angel from the body of someone from Claire's past, forcing him to ask Claire and Michael's sister for help. Riesen moves to consolidate his power against Whele. Worried that his father is close to exposing Gabriel's underground acolytes, William takes extreme action.
Gabriel finds a way to infiltrate Vega, slaughtering a group of higher angels secretly living among the human population. William tries to sway his father while nursing him back to health, and as Claire's wedding nears Alex finds solace in the arms of another.
The revelation of Michael's secrets drives him out of the city, where he and Alex hatch a plan to corner and kill Gabriel -- putting Noma's life on the line. Following Claire and William's wedding her father plans to leave the city, and Gabriel walks into Vega and surrenders.
