I love watching Serenity and am saddened that the movie didn't reinvigorate the Firefly series as people had originally hoped. Still it's a fantastic cap to the series that exists that brings great conclusions to the arcs of River's and Mal's character stories (especially Mal, as a person who loses his faith in the first episode of the TV show and finally restores his belief, if not in religion, by the end of the movie). These arcs are much clearer when watching the entire season and cap in one day. If you haven't done this yet, I highly recommend it.