One might not immediately think this year’s “over 60”-geared comedy/drama The Best Exotic Marigold Hotel lends itself to a sequel, but the film was a sizeable succcess, garnering positive reviews and netting over $130 million at the box office.  As such, development on a follow-up recently got underway with Ol Parker (who wrote the first film) penning the script and John Madden poised to return to direct.  Cast members Judi Dench, Bill Nighy, Maggie Smith, and Tom Wilkinson are all expected to return, and now a couple of newcomers may be added to the list: Helen Mirren and a young whipper snapper by the name of Colin Firth.Per Showbiz 411, Firth and Mirren are "likely additions" to the cast.  The story will apparently continue the adventures of the older crew in India, though no details regarding Mirren or Firth’s characters are given.  Producers are also said to be looking for an American actress to round out the cast.