I can't really remember most of the details. But, basically, some type of tragedy hits the Warblers. I THINK it was a shooting, but I'm not sure. It could have been something else. But, whatever it was that happened basically killed a few of the Warblers, and at the end, they put on a performance. All the warblers who are left alive are standing up on stage and there are empty spots where the others should be. In those spots are the pictures of those who died, and the surviving warblers say a few words about their dead friends and then they sing a song.
I know that's not a lot to go by, but that's all I can really remember. But, I DO know that Kurt wasn't one of those who died. I remember him speaking for one of the dead as well. And I think ND was in the audience for their performance. Hope my tags are right.