Silent movies are giving way to talking pictures -- and a hoofer-turnedmatinee idol (Gene Kelly) is caught in that bumpy transition, as are his buddy (Donald O'Connor), prospective ladylove (Debbie Reynolds) and shrewish costar (Jean Hagen). The musical masterwork Singin' in the Rain is celebrated with special features that salute not just this all-time favorite but also the musical legacy of its producer, songwriter Arthur Freed.