Only now does it occur to me... EVERGREEN (1934)

Only now does it occur to me... that in the midst of an otherwise traditional 1930s musical (the British classic, EVERGREEN), we'd take a hard left turn into a World War I flashback fantasy

 
that's an extended homage to German expressionist auteur Fritz Lang––particularly his masterpiece METROPOLIS (1927)––




which feeds us this majestic sci-fi imagery for about two minutes, including one amazing tableau (women forged into bullets)


that may have even inspired the H.R. Giger piece, "Birth Machine" (1967).

For reference, the rest of the movie takes place pretty much on stage/backstage at realistically depicted British music halls from the 1930s.