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“These flashes make me horribly anxious,” said Helen Mirren (in Michael Kors) as she arrived at the Tribeca Grand Hotel for a New York City screening of The Debt. Despite her nerves, Mirren pulled off some gorgeous poses alongside co-star Jessica Chastain (in Dior). Click through the gallery to see Demi Moore, Paul Rudd and more stars at last night’s hottest parties!