A ll the lonely people … where do they all belong? YouTuber Kane Parsons makes his feature directing debut with this icily brilliant and genuinely disturbing conceptual horror film based on his web series , and scripted by Will Soodik. There is something here of J-horror, the V/H/S found footage franchise, Dan Erickson’s Severance and Nathan Fielder’s The Rehearsal. It’s about people walled up in their own memories, imprisoned in endlessly remembered scenes from their past, or miserably perceived versions of their present existences in which they have become caricatures of themselves, gargoyle stars of their paralysed inner world of failure. Or perhaps the action of the film is not metaphorical in this or any other sense, and the “backrooms” of the title simply exist.…