“ Backrooms ” is one of the most unique cinematic events of the year. The film, which opens in theaters Friday via A24, was directed by 20-year-old Kane Parsons , who previously developed the web series of the same name. Already tallying huge box office numbers from Thursday preview screenings, it is projected to be one of A24’s biggest hits ever. The surreal plot involves Clark (Chiwetel Ejiofor), a furniture store owner who finds a secret doorway that leads him to a seemingly endless series