Epic sci-fi adventure from writer-director Joss Whedon, based on his short-lived television series 'Firefly'. 500 years in the future, after a galactic civil war has united all the space colonies under the repressive Alliance, former rebel soldier Malcolm Reynolds (Nathan Fillion) captains the Firefly class cargo ship 'Serenity', taking on odd jobs and scoring heists where he can to keep his ship and his crew in the air, all the while trying to avoid the attentions of the authorities. When he picks up Simon Tam (Sean Maher) and his disturbed sister River (Summer Glau), Mal ends up with more trouble than he could have bargained for. On the run from the Alliance, River has been the subject of horrific government experiments to develope her latent psychic powers. Determined to get her back, the Alliance dispatches ruthless assassin The Operative (Chiwetel Ejiofor), and Mal and his crew find themselves hunted throughout the galaxy. But when they discover an even darker secret the Alliance would like to keep hidden, they finally have their chance to hit back.