Margot Robbie Didn't Realize She Was Partying With Prince Harry Over the Holidays

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Margot Robbie might play a journalist in Whiskey Tango Foxtrot, but her investigative skills in real life could use an upgrade.

The 25-year-old actress was snapped in a photo booth with none other than Prince Harry over the Christmas holiday, but she told ET she didn't recognize him at first.

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"I didn't know it was him for about half an hour talking to him," Robbie admitted.

The photo booth shot also included Cara Delevingne, Sienna Miller and Suki Waterhouse.

"Suki was having a housewarming party," Robbie explained. "I was like, 'I'll pop in for 10 minutes.' About six hours later the photo booth happened."

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Robbie's co-star Tina Fey joked that the drinks seemed to be flowing plentifully at the event.

"Looking at this picture, I can't imagine why you weren't aware of who was with you or your surroundings," Fey teased.

In the movie, two-time Golden Globe winner plays a journalist sent to Kabul, Afghanistan on assignment. The war comedy is based on reporter Kim Barker's memoir, The Taliban Shuffle: Strange Days in Afghanistan and Pakistan.

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Whiskey Tango Foxtrot opens March 4.