Following the successful destruction of the Beshilu hive, the Ebon Cross take their captive, the Heir of Visions to their sanctum, tying it up in their basement. The creature taunts them with visions of their future. Particular visions include Mammon giving a child to a sworn enemy, Adele standing over the body of a dark haired woman, and the city in flames after something slumbering beneath the city awakened. Deciding against torture and after warning Eric Tenscars, Colt gives his word to free the Heir in exchange for knowledge of his brother's whereabouts. The creature tells them his brother had been traded to a powerful vampire beneath the city, the Plague Nun. He also reveals that Colt's brother James has cancer. After taking samples of the Heir's hair and blood and placing Athaliah in charge of guarding him, they prepare to meet the vampire. Torches in hand, they descend into the tunnels beneath the city while in Twilight. Along the way they encountere a wandering ghost. Though the ghost had only begun to approach, Hope shoots it in the throat with an arrow, driving it away. As the puzzled Mages question her, it becomes apparent Hope was no longer thinking like a rational living person.
They push on, finally arriving at the rough hewn chambers that house the vampire and her minions. Two diseased mortals guard the entrance while playing chess. Meanwhile examining Shadow they see a very different scene. There a vast cavern surrounds a small castle and the roof drips blood. Exploring further they find a small alter with symbols of a heretical sect from the early Roman Catholic Church. In shadow this is a mighty cathedral. They quickly completed their exploration of the remaining rooms in the Fallen realm, encountering the diseased lepers and a vampiric goth who haunts the place. They push into the solid stone coterminous with the Shadow castle. There they run into the small woman in a blood stained habit. This Plague Nun quickly noticed them and began to speak to them. While Adele sneaks past through a wall, Mammon begins to bargain in Latin with the ancient monster. She confirms that she has James but said she needs nothing they have. She also mentions her work to aid the Antediluvians and the approach of Gehenna. Finally, Mammon suggests a service to which she asks for the life of another vampire, Justine Lasky, secret owner of the Discarded Image. Lasky belongs to a group that stole something from her and for that she wants her killed. Colt agrees to the task but first asked to see his brother. Adele hides after hearing the Nun's approach and Colt is able to confirm it is his brother as well as his illnesses.
The cabal immediately begins to investigate the club and its owners. Through his contacts Mammon quickly learns the place is owned by a Tina Bortz. The club is a weird place with mirrored glass on the walls, scoured so everything was distorted and hard to see. Adele and Colt look into the owner in Twilight. She is relatively normal woman with a disturbing habit of slitting her wrists. Meanwhile Mammon and Valkyrie spies on the few patrons of the club, some of whom have the dead auras of vampires. The next day the entire cabal goes there in Twilight. Again they see the vampires, in broad daylight! They quickly identify the woman Mammon and Valkyrie spotted the night before as Justine and proceed to follow her. Creepily she seems to be a living human but with the dead aura and taint of a vampire. By evening they follow her to a highly guarded penthouse apartment. As they stand intangibly over her bed, considering her murder, Adele asked that they looked deeper into whether she is an evil creature so they can be sure it is the right thing.
While Colt confirms her vampiric status after several days of tailing her in Twilight, the others investigate the strange symbols they found in her room. The repeated references to the crescent moon and serpent turn up extensively in Chicago and elsewhere in the world. Starting around the turn of the century, a stylized representation appeared in Chicago, appearing in speakeasies, art buildings, and the recently renovated Uptown theater. They even find a reference to a Circle of vampires in a letter by a friend of occultist and gangster Dion O'Bannon. They apparently have some sort of stone god that they worshipped and have their fangs deep into the city's power structure. Eventually Colt returns with information on her bloodsucking habits and on a special ceremony on the new moon 4 days hence at the Uptown theater.
After some debate, the cabal decides to attend the ceremony to assure themselves of the Circle's ill intentions. As they arrive at the Uptown Theater they see the gathering is quite large with many vehicles present and an armored car. Inside living vampires and normal humans tainted with death energies gather for a religious ceremony. A red eyed woman called the Elder orates while the group hides quietly invisible and in Twilight. One mortal is led up to the alter on stage while an undead vampire is brought in from behind stage in a steel cage. Then they reveal the Antediluvian, a mass of calcified blood radiating power. Under their combined Mage Sights it reveal potent spiritual powers, an undead nature, and the power of a minor deity. As they watch it wrench the soul of the initiate, Starla, from her body and something tattered but similar from the vampire. Then it exchanges them, turning Starla into a blood hungry living vampire and leaving a tormented vampire with a soul. Seeing enough they begin to leave, breaking out into a run as they feel the Antediluvian reach out for their souls.
After escaping the cabal plot their assassination of Justine Lasky. Valkyrie will hush the noise within the room, while Colt applies chloroform and Mammon drags her into a Twilight gate created by Adele. Unfortunately as they attempt this she wakes and begins to struggle. She uses her vampiric powers to cause Colt to abandon the fight but not before Mammon thrust her into Twilight. She throws him off of her and tries to reach the gate before it closes only to find Valkyrie guarding the entrance. Trapped, she is shot in the back by Adele, nearly killing her. She turned her gaze on the young Mage, disarming her with love and guilt. But Mammon sneaks up on her and knocks her out while Valkyrie finishes her with a katana to the heart. The creature killed and the cabal's consciences somewhat shaken, they leave, burying the body on holy ground in Twilight.