Alert, alert! According to Sci Fi Wire, "Most of the cast of...Serenity...have signed on for two more movies." Though star Nathan Fillion isn't officially included in that "most," Whedon himself has said that the whole cast is likely to be back for more - if there is more. Woo hoo! Do a Whedon dance of joy! Wait. Did you say "if"? Yes, friends, there is a caveat here:  logically, there will only be Serene-er and Even More Serene if Serenity itself is a hit. So start chartering vans and offering sexual favors and cash to your friends:  if this thing opens at the top of the box office, Joss is golden.