Von Trier draws his characters and setting with such clarity and particularity that his actors are liberated to do the best work of their careers: Kirsten Dunst in particular, but also Charlotte Gainsbourg, a marvel of frantic energy. The film builds to a final half-hour as gripping and terrifying as any in memory. I saw a lot of movies in 2011. A few, I experienced. Only "Melancholia" blew me to the back of the theater.