JOSS WHEDON has had a curious career. He broke into movies by writing the script for the 1992 film Buffy the Vampire Slayer. The movie, directed by Fran Rubel Kuzui, was something of a disaster. Five years later, Whedon brought the Buffy concept to television, where it met with enormous success and established him as a first-team TV talent. In 2002, Whedon launched a series called Firefly; it was cancelled after only a few episodes. And now Whedon has taken the Firefly concept and turned it into his big-screen directing debut with the movie Serenity. If Serenity succeeds, then good for Whedon. But the question remains: Why in the world would Universal hand a small fortune ($40 million) to an unproven film director for a project based on a failed TV series?

The answer--please grab hold of something solid--is simple: merit. Firefly was an underappreciated gem which felt more cinematic than serial. The translation to the big screen only improves an already exceptional product. Of course it doesn't hurt that Serenity is an ingenious commercial creation which, for devoted fans, serves as a series finale and, for the uninitiated, serves as an enticement to buy the Firefly DVDs.

It is a difficult balancing act, appealing to both of these audiences. As M.E. Russell reported in June, the producers have been very conscious of caring for their base, holding dozens of screenings for the die-hards even while the movie was still a work in progress. Then this past week, Universal tried a slightly gonzo marketing attack by giving free screenings to bloggers in an attempt to build word of mouth among non-fans. We'll know by Saturday afternoon whether or not Universal has made the sale.

What we already know is that Serenity is an uncommonly good movie.

FIRST, SOME NOTES for those who blinked and missed Firefly during its brief run on Fox. Firefly and Serenity are space Westerns, set in the distant future after man has left Earth and colonized another solar system, terraforming a gaggle of planets and moons. As the settlement progressed, some of the outer planets wanted to break away from the central government, the Alliance. These Independents eventually went to war with the Alliance--and lost.

Firefly begins in the waning days of this civil war with the Battle of Serenity Valley. Whedon's galactic civil war parallels the American Civil War down to nearly every detail. The Alliance is more urban and wears gray; the Independents are a rag-tag bunch called Browncoats. The Battle of Serenity Valley is like Gettysburg--the high point of the rebellion; after the Independents are defeated there, the war turns quickly against them. Most important, however, is that the Alliance isn't an Evil Empire--they're the good guys.

So naturally Whedon made the show's protagonists a group of defeated confederates who, being on the losing side of Reconstruction, decide against joining respectable, unified society and take to a life of petty crime out on the frontier planets.

The leader of the gang is Mal Reynolds (played by Nathan Fillion), a former sergeant in the Independent army who captains a smuggler ship he christens Serenity. At first glance, Mal has the air of Han Solo, but he's a more direct descendent of Paul Newman's Butch Cassidy: He has something approximating a heart, he would rather run than fight, and, when the issue is forced, he prefers not to fight fair.