A correction was made to this review on Aug. 23, 2005.

“I am a leaf on the wind: Watch how I soar,” says one character in “Serenity” before being promptly made earthbound. The same could be said of this feature bow by writer-director Joss Whedon, creator of “Buffy” and “Angel” as well as cult TV sci-fi oater “Firefly,” of which current item is a bigscreen continuation. Quirky blend of Western elements, high-end pulp philosophy, decorative Orientalia, old-style frontier dialogue and straight space shenanigans bounces around to sometimes memorable effect but rarely soars. Whedon’s sizable fan base will turn out in droves but this will need a hefty marketing push to post galactic returns.

Following its world preem at the Edinburgh fest, pic goes out wide Stateside Sept. 30, a potentially risky gambit for a cult-fueled venture that would benefit from more time to build beyond its card-carrying audience. Though the widescreen movie contains a reasonable amount of action sequences, it was clearly made with considerably less coin than tentpole studio fare, and still shows a TV-style aptitude for soundstage sequences separated by occasional exteriors.

The Fox network axed “Firefly” in December 2002 after only 11 of the 14 completed episodes had aired. Series went on to immediate cult status on ancillary, and most of the key actors reprise their roles here. Major addition to the cast is Brit thesp Chiwetel Ejiofor (“Amistad,” “Dirty Pretty Things” and upcoming “Kinky Boots”), who darn near steals the movie as the good guys’ ruthless nemesis.

Familiarity with the original episodes isn’t necessary, as a tight opening effectively recaps the backstory. We’re 500 years in the future, following a war in a newly colonized solar system that was won by a coalition called the Alliance; the losers, the Independents, roam the outer planets like frontier cowboys, along with the Reavers, thugs who eat their enemies live.

In an interesting idea that largely lies undeveloped — and has some contempo relevance in a globalized world — the Independents hate the Alliance because the latter are “in their homes, in their heads, (and) tell them what to think.” The Alliance is also inside one particular head — that of River Tam (Summer Glau), a 17-year-old telepath whose brother, Simon (Sean Maher), rescues her from Alliance boffins and security high-up the Operative (Ejiofor) in a pre-credits sequence that’s one of the best in the picture. Tone lightens as the main story and cast show up. Simon was helped in his mission by Capt. Malcolm “Mal” Reynolds (Nathan Fillion, channeling a combo of Harrison Ford and the late Eric Fleming from “Rawhide”), who heads the crew of Firefly-class spaceship Serenity, a rusty-bucket transport vessel. Also on board are his deputy, Zoe (Gina Torres), similarly dressed and holstered like a cowboy; Zoe’s husband, Wash (Alan Tudyk), the craft’s ace pilot; gruff gunslinger Jayne (Adam Baldwin, in a good impression of Warren Oates); and corn-fed farm girl Kaylee (Jewel Staite), the ship’s mechanic.

Main action sequence, realized like a space-age stagecoach-and-Injuns chase, comes early on, as Mal & Co. pull off a payroll robbery on an outer planet and are disturbed by Reavers. Thereafter, most of the action is confined to futuristic interiors — handled OK but, excepting a late-on mano a mano by River, with no special atmosphere.

Pic’s appeal lies in other areas, from its mimicking of period, stately Americana in the dialogue (Mal: “No more runnin’; I aim to misbehave”; Jayne: “She is starting to damage my calm”) to the plot itself. Latter leads Mal & Co., via River’s half-buried memories, to an uncharted planet called Miranda, wherein lies a terrible secret that the Alliance would like to remain buried.

Hot on their tails at all times is the Operative, plus assorted hungry Reavers. Oh, and there’s also Inara (Morena Baccarin), a professional “companion” for whom Mal still carries a torch.

Nobody seems to have told Whedon that many U.S. sci-fiers were already Westerns in futuristic dress, and that cross-cultural Eastern-Westerns were invented 40 years ago. What may have seemed fresh on network TV doesn’t look quite so fresh on the bigscreen.

Still, what makes “Serenity” refreshing is its avoidance of CGI, which gives the pic a much more human dimension; the evident chemistry between the cast; and a humor that doesn’t rely simply on flip one-liners. None of these smarts, however, may be enough to satisfy mass auds.

Fillion makes a commanding enough lead and is neatly backed up by a buff Torres as his femme sidekick, especially in a hold-the-fort sequence that recalls Jenette Goldstein’s character in “Aliens.” Staite brings welcome fragility to the hard-assed crew as the tomboy mechanic, and former ballerina Glau brings neat moves to her action moments.

Sets look considerably airier than in the TV series, though Whedon directs his interior sequences in a visually constricted way that shows his small-screen origins. Colors have a mostly dark, unappetizing look that becomes a tad wearisome over two hours, and David Newman’s score does the business but never elevates the material.