The series follows Joshua Nolan (Grant Bowler), his adopted alien daughter Irisa (Stephanie Leonidas), and the town's new mayor, Amanda Rosewater (Julie Benz), in addition to an ensemble of actors portraying different characters in the growing town[2] in the city-state of Defiance, built on the ruins of St. Louis.

[citation needed] On March 1, 2016, Trion Worlds announced a major update for the game, promoted as season four of the show.

These events resulted in the destruction of most nation-states and the accidental and uncontrolled deployment of Votan terraforming technology, which radically altered Earth's landscape and mutated its ecosystems.

Defiance is a melting pot of human and alien cultures and insists on remaining neutral between the Western hemisphere's two major nation-states: the human-dominated Earth Republic, centered in New York City, and the alien-dominated Votanis Collective, headquartered in Brazil.

Bowler plays Joshua Nolan, "the law keeper in a bustling frontier boomtown that is one of the new world's few oases of civility and inclusion.

[38] On March 8, 2012, it was announced that Julie Benz, Stephanie Leonidas, Tony Curran and Jaime Murray had been cast in the series.

[2][10][37] For season 1, linguist David J. Peterson developed two full languages for the different alien races, for the Castithans and the Irathients.

Bear said that he had to be sure that each version (for the series and the game) had its own unique characteristics, suited to its needs, but also that musical threads united the franchise.

"Heavy synths and ethnic soloists played a key role in defining the sound of Defiance, but the cinematic quality came from working with a string orchestra.[...]

[53] Ellen Gray of the Philadelphia Daily News noted that "the TV show may not break new ground ... but it does stand on its own as a watchable sci-fi series, with a Wild West vibe mixed with a bit of "Farscape-meets-West Side Story.

"[54] David Hinckley of the New York Daily News gave it one star out of five and found it to be "incomprehensible", but said "if you’re a sci-fi fan for whom this stuff can never be too complex, have at it.