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.

Omec hunts Defiance citizens; Nolan, Amanda, and the others undertake a potential suicide mission to end the threat once and for all.

The fate of Defiance hangs in the balance; Nolan must fight against the republic and old friends to stop Irisa.

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 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 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.

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.

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 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.

T'evgin comes to Defiance seeking his daughter, who Nolan and Amanda offer to release in exchange for some gulanite; at the same time, Alak and Pilar head off alone to protect the baby; and Datak and Stahma are threatened into helping Gen. Tak's assault.

Nolan, Amanda and Irisa search for a way to stop Kindzi from transporting more Omec to Earth; Datak tries to escape from an Omec compound; Stahma asks for forgiveness.

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.

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.

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.

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 freed from custody; Amanda, Irisa and Berlin try to release Nolan from Kindzi's clutches; Datak regrets seeking help.

The citizens of Defiance prepare to cast their votes for mayor; Nolan’s past violently rears its head; Irisa must decide whether or not to embrace her destiny.

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.

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.

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.

A deadly plague threatens the town; racial tensions rise when the Irathients, who are immune to the virus, are quarantined.

Nolan's desperate search for Irisa yields vital information which takes him south; back in Defiance, the Earth Republic has installed Mayor Pottinger, a charming, calculating and ambitious man who takes control.

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.

A visiting arms dealer divides Amanda, Nolan, and Berlin. Nolan recruits a militia, but the people need convincing. Datak and Alak have a reckoning. Stahma's presence causes strife.