"Candy-colored" and "joyous" are hardly words you'd use to describe the cinema of the Eastern Bloc, but movie buffs and lovers of high kitsch alike will be surprised by the subject of East Side Story: socialist musicals. Inspired by their American counterparts, a handful of determined artists imported the style of Fred Astaire, Doris Day, and Annette Funicello under the only government-approved theme, "happiness through work." What emerged were priceless curiosities like Tractor Drivers (USSR, 1939), a spirited Industrial Age romp that looks like Earth redubbed by Rodgers & Hammerstein. Only 40 musicals were produced in as many years, because censors hated the bourgeois conventions of the genre, and because audiences understandably balked at titles like Cossacks Of The Kuban River (USSR, 1946) and Ernest Thalmann, Class Leader (GDR, 1955). But despite old equipment, minuscule budgets, and other discouragements, the filmmakers pressed on and gradually improved; one of the pleasant surprises of this documentary is how the later clips are genuinely toe-tapping and hummable. With these musicals and a number of well-chosen talking heads, East Side Story director/narrator Dana Ranga provides a fascinating window into Communism, which failed in part because it never sparked the fantasies of its people. A chorus like, "Racka-dacka! Racka-dacka! We sing the song of the coal press" may have the required ring of propaganda, but it isn't much fun.