Set on a future Earth, Defiance introduces players and viewers to a world where humans and aliens live together on a planet ravaged by decades of war and transformed by alien terra-forming machines. It centers on Jeb Nolan, the law-keeper in a bustling frontier boomtown that is one of the new world’s few oasis of civility and inclusion. Nolan is a former Marine who fought in the alien conflict and suffered the loss of his wife and child in the war. The trauma transformed him into a lone wanderer in the wilds of this new and dangerous world.
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.
Irisa returns to Defiance and is arrested; Mayor Pottinger offers Nolan her release in exchange for capturing those responsible for nearly killing him; Stahma plots to keep Datak behind bars.
Irisa’s terrifying black-outs escalate, driving a wedge of secrecy between her and a worried Nolan. Meanwhile, the Tarr family business thrives under Stahma’s self-appointed direction while an increasingly suspicious Datak remains in jail.
After his caravan is viscously attacked in the badlands, a badly shaken Pottinger orders Nolan to hunt down and destroy those responsible. Nolan’s manhunt implicates one of Rafe’s miners causing tensions to explode.
Amanda is terrorised by a stalker but the true reasons behind her frightening experiences have far reaching ramifications not only for her but for Pottinger and Doc Yewll as well.
After an Arkfall crash, Pottinger recruits Nolan to lead their salvage mission but his secret agenda puts them in grave danger against an Alien race they’ve never encountered before.
Datak is framed for a bizarre murder and turns to an unlikely ally for help; Irisa discovers more about her destiny after encountering a mysterious stranger.
Nolan interrogates a suspected Votanis Collective spy in order to prevent a catastrophic terrorist attack on New York.
Kenya’s earth-shattering return continues sending shock waves through Defiance as Stahma tries to reconcile Kenya’s reappearance, while Doc Yewll works to keep her own dark secret hidden.
Nolan and Rafe race against the clock to rescue Amanda and Pottinger trapped in a deadly mine collapse.
With Nolan searching for Irisa, Amanda is forced to take on the badge as Deputy when the shocking murder of one of their own rocks Defiance.
Nolan races to save Tommy’s life and stop Irisa before her growing forces can put their devastating plan into motion. Meanwhile back in town, Amanda learns the heart-breaking truth about her sister’s murder leading to a daring showdown between Amanda and Stahma.
Nolan and Irisa are mysteriously rescued from their underground confinement just in time to discover that enemy forces are marching on the town of Defiance, which has fallen on hard times following the collapse of the gulanite mines. Meanwhile, Datak, Stahma and Rafe run into deadly complications on their quest to reunite their family; and Alak comes to realize just how unstable her mother-in-law is during their journey through the woods.
Nolan and Amanda are captured while excavating a buried weapons cache; Berlin investigates a Votanis Collective bombing in the heart of Defiance and sees an opportunity to get revenge on Irisa; Stahma's clandestine relationship with the mysterious Omec leader T'evgin takes a turn.
Amanda and Doc Yewll must enlist the Omec for help rescuing Nolan and Irisa, who have fallen into an unexpected and potentially fatal tour of their own past. Meanwhile, Datak and Stahma prepare a decisive move against Gen. Rahm Tak, leader of the Votanis Collective.
Nolan and Berlin pursue the Tarrs after their connection to the Votanis Collective is exposed; at the same time, Alak comes to grips with his future as a father.
A visiting arms dealer changes Defiance's fortunes, and divides Amanda, Nolan and Berlin; at the same time, Nolan encounters difficulty recruiting a militia to fight the oncoming Votanis Collective army. Elsewhere, Stahma's presence causes strife among the mysterious Omec; and Datak and Alak have a reckoning.
Amanda decides to ignore Nolan's skepticism and welcome an encouraging Votanis Collective delegation to Defiance. Meanwhile, Stahma's loyalties are tested by an unexpected arrival; and T'evgin takes another step towards acclimating to life on Earth.
Nolan is unexpectedly freed from Votanis Collective custody, at which point Amanda, Irisa and Berlin rush to save him from Kindzi's clutches. Elsewhere, Datak regrets seeking Doc Ywell's help against the Omec; and something startling is witnessed in the mines.
Nolan, Amanda and Irisa search for a way to stop invulnerable Kindzi from waking and transporting more Omec to Earth; Datak seeks escape from a deadly compound; and Stahma implores Alak for forgiveness before it's too late.
Omec hunts Defiance citizens; Nolan, Amanda, and the others undertake a potential suicide mission to end the threat once and for all.
Amanda negotiates with the Omec, a new alien race, for the future of Defiance; and the Tarrs return to find much changed and their loyalties tested between the humans, the Omec, and the Votanis Collective. Meanwhile, Nolan and Irisa encounter a survivor of Votanis Collective atrocities that can aid their first strike against Gen. Rahm Tak's oncoming army.
Defiance is under siege. As Nolan, Amanda, Irisa and the militia defend the town against the Votanis Collective, Datak recalls his father's chilling lessons and makes a pivotal decision, while Stahma takes an unexpected trip.
A gruesome murder is committed by an unusual beast that's on the loose and being hunted down by Nolan and Irisa, while Doc Yewll delves into the surprising victim. Elsewhere, Amanda resists welcoming back Stahma; and T'evgin learns an unsettling truth about his daughter.
The arrival of the mysterious Nolan and his charge Irisa to the town of Defiance marks a threat to the fragile peace that exists between the residents in the premiere of this futuristic drama, which is set in the year 2046, more than 30 years following a war between humans and aliens that left Earth forever changed.
Nolan and Datak clash over an ancient ritual, while the hunt for a killer is on.
Irisa is forced to confront a disturbing power; at the same time, Defiance is invaded by a swarm of menacing Hellbugs.
Kenya is kidnapped, while Rafe moves a step closer to learning the truth about his son's death.
Irisa faces a threat from her past while Nolan and Amanda lead an expedition outside of Defiance.
An old war buddy catches up with Nolan at the same time a Castithan criminal with a history of violence enters the picture.
Interesting relationships develop when the residents of Defiance are forced to stay indoors as a threatening Razor Rain storm approaches. Meanwhile, visions lead Irisa to the Spirit Riders and Sukar, who has fallen under the influence of a strange and mysterious force.
Following the big storm, Nolan and Tommy find an American astronaut who has been in an induced sleep for the past several decades.
A deadly plague threatens the town; racial tensions rise when the Irathients, who are immune to the virus, are quarantined.
The town of Defiance is shocked when the remains of a leading businessman who went missing almost six years ago, are discovered hidden in the walls of the NeedWant.
Amanda’s mayoral campaign is threatened when Nolan is involved in an accident on the eve of the election, prompting the town to question Amanda’s decision to appoint him as Lawkeeper.