Cosmo Brown (Donald O'Connor) sings about the merits of being a comedic actor in "Singin' in the Rain" (1952). Cast: Gene Kelly, Donald O'Connor, Debbie Reynolds, Jean Hagen Director: Stanley Donen, Gene Kelly "It's not easy working with a genius - but Gene was very patient with me." -Donald O'Connor (1988) on his "Singin' in the Rain" co-star, Gene Kelly Donald O'Connor Interview for Warner Home Video ("Singin' in the Rain" 50th anniversary): -Your signature number in "Singin’ in the Rain"…