I watched this the other night as well, noticed it was coming off Amazon Prime 'soon' so I thought I might as well give it a go. Koreans make heavy allegories about following authorities unquestioningly and looking out for others vs being selfish. Also a lot of people get et by zombies. This was pretty funny. I don't think it necessarily needs or stands any deeper analysis than that though. I loved the long shots of the train arriving into rail yards.