Eph and Nora fight to save Captain Redfern's life before coming face-to-face with the horrifying effects of the virus. A spike in rat attacks signals Fet that something inexplicable is happening deep below the city. Released from jail, Setrakian begins his own merciless plan to stop the spread of the disease.
A secret autopsy demonstrates the bizarre progression of the mystery virus, prompting Jim to make a startling confession. Eph and Nora race to find the father of the youngest victim of the plane tragedy, but someone unexpected beats them to it. Ansel, in the grip of disease, takes desperate measures to protect his family.
Eph and Nora work on a biological weapon to kill the strigoi, and 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 the control of Kelly.
The strigoi are evolving, becoming faster. Smarter. Eph struggles to improve his failing bioweapon while trying to work through the emotional fallout of the abduction of his son, Zack. As Setrakian and Quinlan attempt to crack the Lumen’s deepest-held secrets, Fet helps a Navy SEAL team in a deadly mission: search for the Master through the underground tunnels of New York.
The Master’s offer to return Zack plagues Eph as he considers taking the deal. Dutch reunites with an old group of friends but begins to question if her safety is better with them or with Fet, Eph and Setrakian. Palmer strives for answers to Setrakian’s secret strigoi blood treatments and discovers he may have a way to acquire it.
The fourth and final season opens when out of the ashes of humanity’s nuclear war, Night Eternal has begun. Haunted by the atrocities committed by his son, Eph abandons NYC for Philadelphia. His solitude is cut short when he encounters new fighters who rekindle his drive to fight back. Tasked by Setrakian, Fet and Quinlan search for a new means of stopping the Master.
Imprisoned as a subject in a strigoi breeding program, Dutch is desperate to escape and find Setrakian. Gus recruits his cousin for the inside job that will put his gang at the top of the new world’s underground economy, but Creem is suspicious of his business partner’s ambitions and a CDC team investigates the outbreak of a mysterious illness that mirrors vampirism.
This animated prequel explains the long, winding history of the Occido Lumen text and just how it may be able to help humanity stand against the Strigoi.