Firefly is an American space Western media franchise created by Joss Whedon and produced by Mutant Enemy Productions.

The franchise is set in the year 2517, after humanity's arrival in a new star system, and follows the adventures of the renegade crew of Serenity, a "Firefly-class" spaceship.

In addition, it is set in a future where the only two surviving superpowers, the United States and China, fused to form the central federal government, called the Alliance, resulting in the fusion of the two cultures as well.

According to Whedon's vision, "nothing will change in the future: technology will advance, but we will still have the same political, moral, and ethical problems as today.

"[2] The franchise stars the crew of the ship Serenity: Captain Malcolm "Mal" Reynolds, second-in-command Zoe Washburne, pilot Hoban "Wash" Washburne, Companion Inara Serra, mercenary Jayne Cobb, mechanic Kaywinnet Lee "Kaylee" Frye, Doctor Simon Tam, prodigy River Tam and preacher Shepherd Book.

[3] Despite its relatively short lifespan, the series received strong sales when it was released on DVD and has large fan support campaigns.

All of the Serenity comics were one-shots or miniseries, as creator Joss Whedon didn't believe the Firefly universe could work as an ongoing format without compromising the quality of the franchise.

[13] In February 2018, it was announced that Titan Books would be releasing three new Firefly novels, beginning later that year, with Joss Whedon attached as executive editor.

Generations (Tim Lebbon) was originally scheduled for October 2019 but delayed to November 2020, while Life Signs (James Lovegrove) was released in March 2021, Carnival (Una McCormack) in January 2022 and What Makes Us Mighty (M. K. England) in July 2022.

The next short story, "Haven and Hell", was released in 2020 in the Barnes & Noble and Forbidden Planet exclusive hardcover editions of The Ghost Machine.

Though an unauthorised volume produced as part of the SmartPop Books series, it was edited by Firefly writer Jane Espenson.

In 2015 Toy Vault released a cooperative board game, Fistful of Credits, with three scenarios inspired by the episodes "The Train Job", "Bushwhacked" and "Ariel".

[29] On October 4, 2007, Alan Tudyk said that sales of the then newly released Serenity: Special Edition DVD had led to "talk [of] doing another movie".

The theme song of the series, "The Ballad of Serenity," was written by Joss Whedon and performed by Sonny Rhodes.

On December 8, 2006, The Multiverse Network announced that it had obtained the rights from Twentieth Century Fox to develop a massively multiplayer online game (MMO) based on the series.

[36][37] On January 2, 2012, website Ten Ton Hammer uncovered documentation that Multiverse, the team behind both the Buffy the Vampire Slayer and Firefly MMO projects, had ceased operation on both games as of December 7, 2011 due to lack of funding.

However, on January 5, 2012, former members of the Multiverse team announced that they had acquired the source code and were still working to develop a finished product.

[38] On July 18, 2013, it was announced at Comic-Con that a mobile game titled "Firefly Online" would be released in Q3 2014 for Android and iOS.