''It's very strange and unusual and took a lot out of me,'' says Nicole Kidman of director Lars von Trier's latest devastating drama -- part 1 of a planned trilogy -- which casts her as a mysterious woman who moves to a small Rocky Mountain town whose initially welcoming residents prove anything but. ''I'm glad I went into von Trier world, but it was difficult.'' It may also be difficult for audiences: The three-hour film includes brutal scenes of rape and murder, takes place on a stark soundstage, and features minimal props. ''I think this kind of abstract simplicity is something we need right now,'' says the director. ''It's like a vitamin.... Films look very much alike now.'' (The next two installments will look even more different: After ''Dogville'''s divided reception at Cannes last year, Kidman dropped out of part 2 and was replaced by Ron Howard's daughter Bryce Dallas Howard.) Von Trier's producers and distributors, meanwhile, lobbied for a two-hour cut of ''Dogville,'' but to no avail. ''I'm the type, as you can imagine, that whatever I'm told to do, I will not do,'' he says. ''They should have asked me to make a four-hour version!''