The four survivors begin manifesting strange symptoms, but Eph and Nora's attempt to quarantine them is thwarted as the disinformation campaign begins. Meanwhile, in jail, Setrakian receives a surprise visit from an old - a very old - acquaintance.

With Nora gone, Eph reluctantly joins Setrakian's quest in hopes of gathering enough evidence to warrant a citywide quarantine. Fet encounters the unexpected inside the subway tunnels, and a medical emergency threatens Palmer's master plan.

After discovering the potency of ultraviolet light against the strigoi, Setrakian gains a new and unlikely disciple. A quick trip to a Brooklyn convenience store turns into a deadly all-night siege.

Eph races to safeguard his family, only to learn that Kelly is missing. Dutch reveals her role in Palmer’s plan, and Gus is forced to make a difficult decision about Felix.

Eph investigates Kelly’s disappearance and struggles with what he finds. Dutch pursues a plan to retaliate against Palmer, and Fitzwilliam makes a surprising choice.

Setrakian leads Eph, Fet and Nora in the hunt for the Master’s lair. Left behind at the pawnshop with Mariela, Zack risks his safety for Mariela's sake.

Dutch returns with a plan to broadcast Eph’s warning about the vampiric plague. However, they face a new threat when Eichhorst launches his own attack against the pawn shop. Palmer receives a special visitor, and Gus gears up for the on-coming fight but discovers there’s another mysterious factor involved.

Eph and Fet recon for an all-out assault that Setrakian assures them will finally kill the Master. Gus aligns himself with a strange new force, one that may swing the fight in an unforeseen direction.

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.

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 body guard.

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. Eph returns to NYC frustrated but energized to go after the one person responsible for killing his friends.

Eph and Dutch work together to thwart the Master's greatest ally. Justine runs into trouble with the Mayor while Setrakian tracks down the real owner of the Lumen.

Eph must choose between Zack's safety and the safety of the citizens of NYC. Meanwhile, his relationship with Nora reaches a critical impasse, and Gus and Angel assemble an unlikely gang of Sun-hunters.

Setrakian and Fet battle for possession of the Occido Lumen, and gain a surprising new ally. A massive attack imperils Eph, Nora, and Zack's escape from New York.

Things have changed. The infection enters a new phase. Fet wants to celebrate, but Setrakian and Eph are worried there's more work to be done. Justine conscripts a new, unwilling army in the fight while Eichhorst angrily lashes out with a plan to strike back.

NYC is falling. Eph and Dutch frantically race to finish their new device to stop the Master before the city is overrun. Justine, Gus, and Angel fight in one last stand to stop the spreading virus. Palmer extracts vengeance for past wrongs but may have crossed the line.

Humanity teeters on the edge of destruction. The Master finally reveals himself, initiating the end game of a battle in which there can be only one winner. Eph, Fet, Setrakian, and Dutch must overcome their personal differences in a last-ditch effort to vanquish the strain.

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.

Quinlan and Fet discover that stealing a nuclear warhead isn’t easy when they encounter an unexpected enemy. Eph and Alex concoct a new weapon to use against the strigoi. Frustrated with his seclusion, Zack discovers a love interest.

Fet and Quinlan track a convoy carrying their prized nuclear weapon; Eph and Alex search for clues to uncover the Master's plan for the fate of the human race; a familiar enemy traps Dutch, who encounters an old friend as well.

Fet and Quinlan must figure out how to get the nuclear bomb back to New York, while a desperate Eichhorst draws near; love-struck Zack tries to learn more about his new crush, but makes a devastating discovery.

With his health failing, Setrakian ignores Eph's warnings and pushes himself to the limit in his quest for victory and revenge; Fet and Quinlan race back to Manhattan, while the Master seals off the city and prepares to eliminate them all.

Reeling from loss, the heroes regroup; the heroes devise a new plan to track the Master through human collaborators, beginning at the blood farm with someone Dutch knows all too well.

An unexpected guest brings old conflicts to the surface, dividing the heroes and threatening the group's trust; with questionable new intelligence in hand, the group launches a make-or-break final assault on the Master.

In the series finale, Quinlan devises a desperate plan, but the costs are enormous. Eph wrestles with his conscience, Fet undertakes a suicide mission, and Dutch and Gus dig in for battle as humankind makes its final stand against the Master and his Strain.