While Paris Hilton sings karaoke at Park City bars and Ashton Kutcher rides the ski lift with Demi Moore to plug his first dramatic role in "The Butterfly Efflect," numerous films of substance are making their mark. More documentaries than ever are screening at this year's indie fest, including several highly political works. Alison Maclean ("Jesus' Son") and Tobias Perse's "Persons of Interest" investigates the persecution of Muslim-Americans in the wake of 9/11. Ivy Meeropol's "Heir to an Execution" chronicles her effort to come to terms with the lives and deaths of her grand parents, Julius and Ethel Rosenberg. Carlos Sandoval and Catherine Tambini's "Farmingville" looks at immigration, and Jehane Noujaim's "Control Room" examines media coverage of the war in Iraq. There are also dramas that feel like documentaries, including Debra Granik's stark feature film "Down to the Bone," the story of a mother's battle with drug addiction.

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