Firefly

First of all, relax: Joss Whedon’s space-western thingie "Serenity" can be enjoyed even if you’ve never heard of "Firefly," the short-lived Fox series from which it sprang.

That said, if you do happen to be intimately familiar with the adventures of Mal Reynolds and his ragtag crew of 26th-century space cowboys, forever offending the military Alliance and evading the fearsome Reavers, you’re gonna have a ruttin’ good time.

Whedon has taken some pains to make sure his movie can stand alone, nimbly opening the action with just enough backstory to fill newbies in on the action while introducing "Dirty Pretty Things’ " Chiwetel Ejiofor as a new nemesis for perpetual rebel Reynolds (Nathan Fillion), having targeted the mysteriously messed-up young woman (Summer Glau) who’s taken refuge along with her doctor brother (Sean Maher) aboard Reynolds’ beat-up little spacecraft Serenity.

"Serenity," the movie, flies about as smoothly as its namesake - which is to say, it’s an inelegant machine, but a sturdy one. Whedon makes the most of the widescreen frame in several space battles, and gets a genuine movie-star performance out of Fillion, who’s allowed to get a little meaner and a little darker as the hot-and-cold-blooded hero, and the story’s focus on Glau gives her the chance to do a lot more than she ever got to do as the show’s cryptic McGuffin.

The inelegance comes in where the script is concerned; while it does answer several big questions left dangling when the show was cancelled, it does it in a slightly lumpy way that feels kind of bumpy, like a two-part episode of the series inflated to feature length. Several cast members - especially Ron Glass’ Shepherd Book and Morena Baccarin’s Inara - aren’t given very much to do from scene to scene. And die-hard Whedon fans will catch him repeating himself here and there, like a last-stand sequence that feels a lot like the series finale of "Buffy the Vampire Slayer."

Of course, inelegance was a big part of the show’s charm, and it’s perfectly acceptable here. Fans of the show will be inclined towards forgiveness, and first-timers probably won’t even notice the tics. They’ll just be watching a cool space western thingie. Thus: Yee-hah.

Universal’s enhanced-widescreen DVD includes a four-minute video introduction from Whedon, and his running audio commentary is essential listening, but the rest of the extras are surprisingly thin: Two of the three production featurettes don’t actually address the making of the movie - one delves into the underlying mythology of the "Firefly" universe, while the other celebrates Whedon and his cast’s appearance before rabid fans at the San Diego Comicon - while the third is a disappointingly superficial making-of.

True-blue Browncoats will delight in nearly 15 minutes of deleted and extended scenes, and a giddy six-minute blooper reel. And there’s always Fox’ "Firefly" boxed set, if you’ve a hankerin’ for further features.