VENICE, Italy (AFP) - Cinema enthusiasts are descending on Italys floating city for the 68th edition of the Venice Film Festival, which kicks off on Wednesday with George Clooneys hotly anticipated Ides of March. Twenty-two films all world premieres will compete for the prestigious Golden Lion award, with a host of stars expected on the red carpet, from the blue-eyed Clooney to US singer Madonna and The Godfather star Al Pacino. Highlights include Swedish director Tomas Alfredsons adaptation of John Le Carres Cold War thriller Tinker, Tailor, Soldier, Spy, starring Gary Oldman and Colin Firth, and Canadian director David Cronenbergs A Dangerous Method. The latter, starring Keira Knightley, Michael Fassbender and Vincent Cassel, tells the tale of the tempestuous relationship between psychiatrist Sigmund Freud, his pupil Carl Jung, and a bewitching woman who comes between them. Cronenberg, known in his early horror film days as the Baron of Blood, has described the story as a strange menage a trois... irresistible to do. Sex and tragedy also drive Dark Horse, about a pair of thirtysomethings with arrested development, which director Todd Solondz has said he made to see if I could make a movie without rape, paedophilia or masturbation.