A tortured Nicolas Cage captivated audiences at the Venice film festival Friday with his performance as a tormented ex-con who seeks redemption in David Gordon Green\'s brutal American South drama \"Joe\". Cage, who won an Oscar for his rendition of a suicidal alcoholic in \"Leaving Las Vegas\", plunges the depths of humanity once more with his performance of wild criminal Joe Ransom, guardian of the lost and helpless. The film, based on American novelist Larry Brown\'s eponymous 1991 novel, takes place in Texas and portrays the desperate lives of poverty-stricken labourers and layabouts in a rough land where violence reigns. Ransom divides his lonely life between drink and his work for a lumber company before he meets 15-year-old Gary, played by \"The Tree Of Life\" star Tye Sheridan, who has moved to the area with his abusive, alcoholic father. Though he struggles to control his inner demons, Ransom reaches out to those in need, taking in a female friend and becoming increasingly close to Gary. Sheridan gives a powerful performance as an earnest, conflicted adolescent who seeks a paternal figure in Joe, but is almost outshone by the on-screen presence of Gary Poulter, a non-professional actor who plays his father. Poulter, who died in March this year, was homeless when he was spotted by casting director John Williams at a bus-stop and persuaded to try for the role. \"We knew we were taking a great risk by choosing a man who had no address or identity documents, but he had a history,\" Gordon Green said. \"We were searching for real vagabonds and Gary had a magnificent look about him, the air of a lost soul,\" he said. Largely set in a wood and the surrounding derelict spaces -- from disused railway tracks to abandoned houses -- \"Joe\" has a paired-down, almost poetic air and uses existing transient locations rather than creating them on set. \"I wanted to keep it authentic. Yes, people really do live in these conditions,\" Gordon Green said about the hovel where Gary\'s family lives. The sense is of an increasingly inhuman, individualist society, peopled with disillusioned characters who further their own ends at any cost -- a metaphor captured by a savage scene in which a dog slaughters and devours another dog. Ransom is the only one who really evokes the possibility of deliverance. Gordon Green said he had been particularly drawn to the possibilities the script offered \"to explore the question of masculinity.\" \"Joe is an admirable man with very fatal flaws, there\'s no greater or more interesting character for me,\" he said. \"The film is about redemption, about easing Joe\'s pain and the pain he has caused to others through the empowerment of this young man,\" he added. A suave-looking Cage, without the rugged beard he wears in the film, said he had been desperate to work with the American director: \"I would do three somersaults backwards naked for him, he is not afraid to bare his soul.\"