The young royal couple walked the red carpet Sunday in the UK premiere of Steven Spielberg's latest film "War Horse."

The Duke and Duchess of Cambridge managed to steal the spotlight from the celebrities of the film as well as the protagonist horse of the film. The Oscar-winning director felt so honored that royals went to see the premiere, which took place on the eve of Duchess' 30th birthday.

"It's an honour to be here with the royals. This is my first royal premiere for the Duke and Duchess, having done them before for the Queen and the Queen Mother. This is a wonderful occasion tonight," said Spielberg.

The couple turned the heads of many, with Prince William looked dashing on his black tuxedo with a bow tie. Kate Middleton looked very elegant in her simple flowing lacy dress and black clutch accentuated by her brunette curls and jewels.

The film includes a British cast comprised of Benedict Cumberbatch, Tom Hiddleston, Emily Watson, David Thewlis and newcomer Jeremy Irvine also walked the red carpet at the Odeon Leicester Square in London on Sunday alongside 600 serving and ex-military personnel.

The premiere benefited the Foundation of Prince William and Harry, which helps the welfare of those in the armed forces.

"War Horse" was adapted from the 1982 novel of Michael Morpurgo, which narrates the story of a boy who tries to track down his beloved horse that was sent to France to serve on the First World War.

The novel was adapted into a play in 2007 and garnered rave reviews and recognition, including five prestigious Tony Awards last June.

The film was released in the U.S. and Canada in December and is seen as one of the prominent contenders in the Academy Awards next month.