Serenity is the film that follows on from the short-lived much much-loved TV series Firefly, which was created by Joss Whedon–the guy behind Buffy. The TV series is a cross between a Western and a Space Opera. It follows the adventures of Captain Mal Reynolds and his crew on board the ship Serenity as they ply their trade–a little cargo hauling, a little thievery–among the outer planets. The series was cancelled after just 13 episodes, but it has gained a large cult audience on DVD, because it is a damn fine show with rich characters, a vivid setting, and Whedon’s characteristic sarcastic humour.

Fans of the series will want to know one thing: does Serenity work, or has it been spoiled by its transition to the big screen? The answer: it works. Whedon has had to make a few sacrifices to make it accessible to people who aren’t aware of the back story, but they’re forgiveable. The biggest is that early on, Mal is prepared to ditch Simon and River, because they have become too dangerous to keep around. This doesn’t square away with his firm insistence in the series that they are indisputably part of his crew–and from the series, we know that Mal is the very epitome of “a man of his word”.

But very quickly, the rough transition from TV to film is smoothed away, and the story is in full flow. River and Simon have been on the run from the Alliance since Simon helped her escape from the top secret institute that had been training and brainwashing her. The Alliance is now getting serious about getting her back, and they have sent a deadly Operative (played by Chiwetel Ejiofor) to hunt her down and bring her back–or kill her–to safeguard the secrets she knows. Can Simon convince Mal to keep helping them? Can they find some way to escape this unstoppable force, or defuse the knowledge locked in River’s head?

Just as the series, Firefly is filled with action: daring rescue scenes, gunplay, and fistfights galore. The characters and dialogue are as rich as ever. The plot reveals a lot of answers about the Firefly universe, and although it would have been easy for Whedon to leave an obvious hook for a sequel, the ending is dramatic and rather final. It doesn’t kill off the possibility of more films, or a revival of the series, but the dynamic would be forever changed. In this sense, Serenity is much more than just a two-hour extended episode. It is a cap on the series, and a thing of its own.

The one thing I really can’t say about the film is how I think it will appeal to you if you haven’t watched Firefly. I suppose it would be a bit like watching the X-Files movie cold, without being aware of its history. Space Adventure. Woo-hoo. But would you think it was anything special? I’m not sure.

Part of Firefly’s appeal is that it was cancelled before it had a chance to get crap. Just like Farscape, it ended while its audience still wanted more. Serenity is a chance to dive back into that universe again, even if just for a few hours. And it doesn’t disappoint.