In the Season 4 premiere, Vincent and Cat's wedded bliss is short-lived when J.T. brings them the news that someone is trying to expose the identities of beasts.
While Eph, Nora, and Zach leave New York City by train, Vasiliy and Abraham bid against Eicchorst to acquire the Lumen.
While Eph and Nora make contact with Zach's grandparents, Lyle threatens Justine with indictment... and turns up dead. Meanwhile, Dutch goes back to Nikki, and Eichhorst tells Eldritch about the true nature of their relationship.moreless
Eichhorst relieves his past in pre-war Germany as he prepares to feed on Dutch. While Vasily, Nora, and Eph search for their missing friend, Abraham meets Rudyard and warns him about the Lumen.moreless
A toxic Black Rain storm over Westerly forces John and Pawter to take shelter in the Royale overrun with a gang of dangerous criminals. Meanwhile, Dutch and D'avin are trapped on Lucy coming perilously close to the eye of the storm.moreless
An arms dealer brings Defiance deliverance, but asks for a drink with Berlin as his only price. Meanwhile, Datak is sentenced to death and prepares for his execution, and asks a sacred favor of his son.moreless
Nolan races to save Tommy's life and stop Irisa; tensions between Amanda and Stahma lead to a showdown.
Nolan fights to save the planet from the arkbrain's terraspheres under Irisa's control. However, E-Rep--and Amanda--are willing to kill Irisa to stop her rather than risk all on Nolan's plan. Meanwhile, Pilar abducts Christie and Alak, forcing Datak and Stahma to rescue Rafe and go after them.moreless
A deadly mine collapse leaves Amanda and Niles trapped, and it's a race against the clock for Nolan and Rafe to save them. Meanwhile, Irisa convinces Tommy to help her steal a terrasphere, while Rafe learns that Quentin has made a deal to free Pilar.moreless
While Nolan sets out to find his missing daughter, Amanda becomes a volunteer deputy to find the murderer of one of her prostitutes.
Kenya returns, much to Stahma's dismay, but she holds a secret locked in her memories. Meanwhile, Dr. Yewll attempts to hide some dark secrets of her own.
When Nolan and E-Rep arrest a VC terrorist in Defiance and try to determine the location of a bomb, the terrorist's compatriot calls Amanda and tells her to free the man... and claims to have her missing sister Kenya.moreless
An Arkfall crash salvage mission led by Nolan leads to danger in the form of an alien race he has never encountered before; at the same time, Stahma makes a shocking power play after she's admonished by church elders for her growing sense of female empowerment; and Irisa begins confessing her deep, dark secrets to Tommy.moreless
A stalker comes after Amanda, raising concerns for both Nolan and Niles.
Raiders steal E-Rep mining equipment and humiliate Niles, and the mayor orders Nolan to find them. The Lawkeeper soon determines that Rafe is involved, forcing the miner to make an impossible decision. Meanwhile, Datak returns to restore balance to his family.moreless
While Irzu's influence on Irisa grows, Niles makes an arrangement with Yewll and Datak realizes that Stahma doesn't want him to come home.
Irisa is arrested upon her return to Defiance, but Nolan can arrange her release by capturing those responsible for an explosion that nearly killed Mayor Pottinger. Meanwhile, Stahma decides the only way to stay in control of her family's criminal enterprises is by ensuring that Datak stays behind bars.moreless
Nolan's search for Irisa leads him to New Chicago and AngelArc. Meanwhile, back in Defiance, the Earth Republic appoints a charming, calculating, and ambitious man named Niles Pottinger as mayor.
During a bicycle race, one of its racer dies, leaving Murdoch to believe he was killed by a mysterious stimulant.
While Defiance citizens cast their votes for mayor, Irisa must decide whether to accept her destiny and Nolan faces his past.
On the eve of the mayoral election, Nolan and Amanda both come under fire when the Lawkeeper is involved in an accident.
The wedding of Alak and Christie is threatened when Rafe realizes what Datak is up to. Meanwhile, a businessman's corpse is discovered in the walls of Need Want and Tommy sets out to find the killer.moreless
A plague strikes down the residents of Defiance. The people blame the Irathients and place them under quarantine, while Nolan and Connor must confront the E-Rep soldiers to get the cure.
Defiance receives a visitor: an astronaut from the year 2013 who has the potential to destroy the town.
Irisa has a vision that a Razor Rain storm is coming toward Defiance. While Nolan warns the townspeople, Sukar is seemingly killed... and then comes back to life and asks Irisa to help him on a holy mission. Meanwhile, Nicky tries to find out what happened to Birch, and Stahma asks Kenya for assistance teaching Alak how to pleasure his bride-to-be.moreless
A former soldier turned bounty hunter pays Nolan a visit while on the trail of a Castithan war criminal, Pol Madis. Amanda wants to use the prisoner as a bargaining chip to get concessions from the Earth Republic, but Madis escapes under mysterious circumstances. Meanwhile, Kenya's feelings toward Nolan cool, and Quentin discovers more about the artifact... and what some people are willing to do to get it.moreless
While Irisa meets a face out of her past, Nolan and Amanda take a trip to deliver scrip for the new maglev branch, only to have their land coach stopped by jackers.
Kenya is among several people that are mysteriously abducted. Meanwhile, Rafe tries to determine who gave his dead son the golden device that may have led to the boy's death.
Two Defiance residents are killed under mysterious circumstances, and Nolan soon confirms that that they were torn apart by mutant Hellbugs. Meanwhile, Irisa is plagued by visions from the past, and Datak and Stahma try to reconcile the situation between Christina and Rafe so that her marriage to their son can proceed as planned.moreless