James Cameron, the filmmaker, and studio 20th Century Fox have declared 21 August to be international "Avatar Day", when cinema audiences will be given a free teaser of his first movie since Titanic. After screening 20 minutes of his highly anticipated 3D sci-fi spectacular, Avatar, to a packed audience at Comic-Con in San Diego on Thursday, the director said that he would take over 3D cinemas around the world for a day to screen 15 minutes of the film for free. There have been claims that Avatar, about a trooper using technology to control an alien body, boasts a new level of 3-D experience.