Nathan Fillion is doing just fine as Castle on ABC, but the series he should have starred in for years, before that, was Firefly, the Joss Whedon outer-space Western in which Fillion starred as the rogue-ish captain of a rebel ship on the fringes of both the universe and the law. Firefly premiered on Fox in 2002, and was canceled after one season – but Whedon stubbornly, and valiantly, revived the franchise for a single, big-screen movie called Serenity, with the same cast, in 2005. It’s quite good, either as a companion to the series or as a stand-alone adventure – and certainly showed that Whedon had a gift for both character and action on the silver screen. And now look at him…