Firefly was a short lived science fiction television series that was cancelled in mid season by FOX. The show had and still has a large following, large enough that a movie was made to continue telling the story. The series is the creation of Joss Whedon, the producer of Buffy The Vampire Slayer. Inspired by a book on the Civil war, the premise of the show is that after Earth’s resources were exhausted, the human race moved to a new solar systems where it terraformed hundreds of worlds. War broke out between the inner planets where most of the wealth was and the outer system poor in wealth and quality of terraforming. The crew of Serenity, a Firefly class spaceship, were on the losing side of this war for unification, the side of the Browncoats who were fighting for their freedom. The crew flys between the various settled worlds taking any job, legal or not, that would keep them flying.
The show was a high quality show. It made people think. IMHO, it is the thinking part that resulted in Fox cancelling the show. After all, they would not want to broadcast a show that was above what they considered the average intelligence of their viewing audience. I believe that Fox vastly underrated their viewing audience. The fans of Firefly, known as Browncoats after the side that crew were on, fought the show cancellation. The campaign was unsuccessful as far as getting the show back on television. The campaign was successful enough for a major motion picture to be made, a previous unheard of event for a movie to be made based on a cancelled television show.