The Duke and Duchess of Cambridge were special guests at the Royal Premiere in London on "Mandela: Long Walk to Freedom," the night of which shocked audience members were informed of the iconic South African leader's passing.

As patrons filed out of the theater, the film's executive producer, Harvey Weinstein, noted that Kate Middleton "was very emotional, she was in tears and very moved by the events. We all were," according to the Daily Mail. "There is nothing to describe the momentousness of what happened. The Duke and Duchess handled themselves very elegantly."

"I spoke to them downstairs in the foyer after the movie. William was deeply touched by the news, you could see it in his face, but he was being very courageous," Weinstein added. The couple had met with Mandela's daughters Zindzi and Zenani earlier in the evening while walking the red carpet. Mandela died at 6:50 p.m. UK time, minutes before the film premiere began, and his daughters were informed right away and asked permission for the screening to continue.

"Zindzi and Zenani left as soon as they heard the news, but they did not want to stop the screening," said Weinstein. "William and Kate said they wanted to watch the movie and stayed until the end. We all did. It seemed the right thing to do."

Prince William even stopped to speak to a reporter and give his condolences.

"I just wanted to say it's extremely sad and tragic news. We were just reminded what an extraordinary and inspiring man Nelson Mandela was," he said the night of the premiere. "My thoughts and prayers are with him and his family. It's very sad."

Today, Dec. 11, the royal couple visited the South Africa House in Trafalgar square to sign the Nelson Mandela condolence book and pay their respects to the former president and anti-apartheid hero. Both kept their outfits appropriately somber, Middleton wearing a two-piece black suit with tiny polka dots, black pantyhose and black pumps, and Prince William dressed in a navy blue suit and purple tie.

Click here to see photos of Kate Middleton and Prince William visiting the South Africa house this afternoon to pay their respects and sign the condolence book for Nelson Mandela.