When Joss Whedon's imaginative sci-fi series, "Firefly," was canceled, fans went into deep mourning. But thanks to their enthusiastic snapping up of the show's DVDs, Universal ponied up $40 million for "Serenity," a movie version that brings back Capt. Malcolm "Mal" Reynolds (Nathan Fillion) and his lovable, outer-space mercenaries.

In the retelling, writer-director Whedon has boiled off a lot of the complexity and introduced a new character, the ruthless Operative (Chiwetel Ejiofor), an agent for the evil Alliance, the Big-Brotherish federal government that runs Mal's galaxy. The result is a sort of amphetamine-fueled reprise, designed to give fans their sentimental jolt but also drum up new devotees. It's entertaining, especially because of Mal's colorful followers, including smart-as-a-whip Zoe (Gina Torres), rednecky Jayne (Adam Baldwin), quippy pilot Wash (Alan Tudyk) and quirky mechanic Kaylee (Jewel Staite).

When Mal allows a pair of young sibling fugitives on board his spaceship, the Serenity, one of them -- River (Summer Glau) -- turns out to be a volatile psychic whose telepathic knowledge is a threat to the Alliance. Then Operative, who speaks gently and carries a big sword, comes in, and if that's not enough, Mal and crew have to keep a step ahead of all those cannibalistic Reavers as all galactic hell breaks loose. Being a mercenary is a crazy business, but, thanks to Whedon's snappy, witty and often poignant pen, it's great fun for us.

-- Desson Thomson