There isn't a single spoken word in The Tribe and all characters communicate in what appears to be a sign language whose authenticity I wasn't able to verify. At first, I was expecting there would be subtitles because, if gestures used were indeed a real sign language, not having them would assume two levels of viewership: those who can understand it and those who can't. That doesn't really seem likely to me. Then I started wondering if the gestures were some fake sign language that no one can really understand and it was like that by design: there is no understandable language used in the movie to move the viewer from a focus on verbal understanding to a focus on gestures and body language.
Is the movie in real sign language? If yes, why was there no subtitles so that those who don't understand it are at par with those who do?