
It's based on the true story of the German sextet the Comedian Harmonists. Half the group is Jewish and half is Gentile. This isn't even something they think about, let alone care about when they form to create a group based on the popular U.S. group the Revellers. They become a sort of subtle-humor-filled a capella group (although one of the sextet is actually the pianist, who accompanies them). The movie is based around the success and subsequent demise of the group, particularly at the hands of the Nazis, who take over and shut down their career because of the Jewish members.

If anything, the flick is worth watching because the music that appears in it is all remastered from original recordings of the group. It's a little awkward to watch, of course, because despite the best remastering work, it still has that old-tyme sound to it. But it adds a lot of flavor to the flick. And at about two hours, it flies by, truly.
PS: If you hate subtitles, my apologies. Most of the flicks I watch have subtitles, because I find some of the best films aren't hammered out in the U.S.