Kate Middleton kept things chic yet sexy at the 2013 Royal Film Performance premiere of "Mandela: Long Walk to Freedom," which she attended alongside her husband Prince William, wearing a floor-length, cream-colored Roland Mouret gown with a slit down one thigh, the Daily Mail reports.

The Duchess of Cambridge braved the bitter December cold to strut her stuff on the red carpet. She wore her French designer cream-colored gown, which she has worn previously at a private dinner in 2012 at the prestigious Thirty Club at the Claridges hotel, along with an eye-catching silver necklace and black sky-high pumps.

Middleton also wore her long brown locks, which she recently dyed a darker shade to cover up her graying roots, swept back in a slick ponytail, to keep the attention drawn to her dramatic necklace.

The new film is based on the life of 95-year-old South African anti-apartheid hero Nelson Mandela (played by Idris Elba), who was being treated at home for a lung infection that had him hospitalized in critical care for three months. He has since passed away, according to South African national TV, leaving quite the legacy behind.

One of Mandela's daughters, Makaziwe Mandela, told UK broadcaster SABC that her father was putting up a "courageous" fight even from his deathbed, "teaching us lessons - lessons in patience, in love, lessons of tolerance," as the Mirror reports.

"Mandela: Long Walk to Freedom," was directed by BAFTA-winner Justin Chadwick, whom the royal couple will meet tonight, along with Mandela's daughter, Zindzi Mandela, members of the cast and crew, as well as Cinema and Television Benelovent Fund trustees and beneficiaries.

Click here to see photos of Kate Middleton and Prince William attending the Leicester Square, London premiere of "Mandela: Long Walk to Freedom."

*This article has been updated to note several changes.