The German actress sang at Glastonbury and acted alongside Philip Seymour Hoffman in his final film. It seems America may soon decide Hoss is boss…Nina Hoss is at that juncture where years of acclaim could tip her over into outright fame. She is two months off 40 and can bank on the admiration of international arthouse audiences, who have seen her in a run of disquieting thrillers by Christian Petzold.