When we think of the American movie musical, we think of its perfect moments. Gene Kelly singin’ in the rain. Fred Astaire and Ginger Rogers dancing cheek to cheek. Busby Berkeley’s insane terpsichorean fractals.
ArtsEmerson’s five-month film series “Gotta Dance: A Survey of the American Film Musical’’ has those moments and more, and if you’ve never seen “Singin’ in the Rain’’ on a big screen, you owe it to yourself to get down to the Paramount Center’s Bright Family Screening Room when the MGM classic opens the series this Friday night and Saturday afternoon. But “Gotta Dance,’’ like most of ArtsEmerson’s adventurous programming, is more welcome for rescuing a number of rarely seen and hardly ever seen early film musicals and bringing them to the Bright in restored prints. They’re not all great films - in some cases they’re instructively bad - but they fill in the blanks of Hollywood musical history in a way the perfect ones don’t. They’re not the apex of the form but the building blocks that got it there.
