George Clooney, Madonna and Roman Polanski are amongst the filmmakers showcasing their work at this year's Venice Film Festival. Twenty-one films will compete for the Golden Lion, with this year's stellar line-up giving festival organisers seemingly more confidence than in recent years. [3]The 68th annual edition of the event features a high-calibre of Hollywood stars alongside heavyhitting arthouse helmers. George Clooney will kick things off with his political drama "The Ides of March". His is one of 12 American films selected, but festival director Marco Mueller denies any favouritism towards his trans-Atlantic counterparts. Venice Film Festival Director Marco Mueller, saying "There is no doubt that when we talk about the films coming to the festival from the United States, we are not talking about main street films which will then come out the next day in cinemas around the world. It's enough to look at our opening film, George Clooney's film, and how much of a sharp film it is." Madonna will premiere her film "W.E." about Wallis Simpson, the American divorcee who's romance with Britain's King Edward VIII lead to his abdication. Venice Film Festival Director Marco Mueller, saying "We have had to tell Madonna and her producers to present their film outside of competition, it is an event on its own. We believe in the film and will give it importance in the programming. And do you want to know who will be the real star of that day? A gentleman called Roman Polanski, who, unfortunately do to legal reasons, on which we could start a debate, will not be present in Venice. But his powerful film will be there, 'Carnage'." Other big names include David Cronenberg's "A Dangerous Method" and "Let the Right One In"'s Tomas Alfredson for "Tinker, Taylor, Soldier, Spy". Al Pacino will be on hand to receive a special award and premiere his documentary "Wilde Salome", which explores the play by Oscar Wilde. "Black Swan" and "Wrestler" director Darren Aronofsky will lead the jury with other stars expected Kate Winslet, Jodie Foster, Keira Knightley and Colin Firth. The festival runs from August 31st to September 10th.