Serenity is both the name of the sequel movie and of the two-part pilot of the series, which was pushed by FOX and broadcast later in favor of a more action-packed episode. Back then it wasn't unusual of FOX to air episodes out of order according to what they thought would attract more viewers. The result, "shockingly", was the opposite.
As for the show itself, I think it's great and I recommend it to everybody who likes science-fiction. The cast is amazing (Nathan Fillion, Alan Tudyk, Gina Torres, Jewel Staite, Adam Baldwin, Summer Glau, Morena Baccarin, all of them as regulars!). I don't consider it "the best thing ever", as many seem to do, because it was so short-lived that it didn't have enough time to see its characters grow and evolve. But it was a great ride and the movie, even if it doesn't feel the same, was a satisfying conclusion to the story.
Post edited July 30, 2017 by Caesar.