Setrakian risks the lives of the entire group to find information about a closely guarded secret text. The Master begins the next phase of his own plan by creating a terrifying new breed of creature and placing them under Kelly's control.
Eph and Nora experiment on their newfound patients. Fet and Dutch grow closer as they clear out the neighborhood buildings, and Kelly begins her hunt for Zack.
Gus and Vaun wage an attack on Palmer as Eph struggles to connect with Zack. Councilwoman Justine Faraldo vows to bring her extermination policies to the other boroughs.
Eph and Nora finally see their lethal virus in action. Fet takes the security of Red Hook into his own hands while Dutch and Setrakian set off for Staten Island to question Fitzwilliam, Palmer's former bodyguard.
Eph changes his appearance to leave the city while Nora is left as the reluctant parent for Zack. Dutch and Nora make a deal with Justine to secure Fet's release from jail.
Eph concocts a plan to make and distribute a bioweapon. Gus realizes Angel can be an unlikely ally, and Kelly comes after Nora and Zack.
Setrakian and Fet use Fitzwilliam's info to attack the Master, but a mysterious new player arrives. Dutch receives a surprise guest. Eph returns to NYC frustrated but energized to go after the one person responsible for killing his friends.
Eph must protect Zack against a surprise intruder into Red Hook. Gus convinces the Guptas to make a difficult choice. Fet and Setrakian set out to acquire the Lumen but discover they are not the only potential buyer.
Justine takes drastic measures to counter a surprise invasion. Nora and Fet perform a useful mission while Eph and Setrakian face off against an old foe.
Dutch helps Eph attempt to assassinate Eldritch. Meanwhile, Abraham, Vasiliy, and Nora search for Rudyard Fonescu and the Lumen, while Justine tells the Upper East Siders the price they have to pay for her help.
Eichhorst relives his past while torturing Dutch in the present, while Vasiliy and the others try to find their friend. Meanwhile, Abraham finally meets Rudyard, and Gus and Angel take the Guptas to safety.
Eph makes arrangements to get the bioweapon to Justine, in return for travel permits to get Zach to his grandparents. Meanwhile, Eichhorst warns Eldritch that the white's effects are temporary, and Gus and Angel travel to Rikers to get a new attack squad for Quinlan.
While Eph and Nora take Zach to the boy's grandparents, Abraham and Vasiliy prepare to bid for the Lumen against Eichhorst. Meanwhile, Quinlan and his Day-Hunters make their move.