In which film did Peter Ustinov play the role of Prince of Wales who later becomes George IV?

Sir Peter Alexander Ustinov (16 April 1921 – 28 March 2004) was an English actor, writer, dramatist, filmmaker, theatre and opera director, stage designer, screenwriter, comedian, humorist, newspaper and magazine columnist, radio broadcaster, and television presenter.

'Beau Brummell' is a 1954 American-British historical film released by Metro-Goldwyn-Mayer. It was directed by Curtis Bernhardt and produced by Sam Zimbalist from a screenplay by Karl Tunberg, based on the play Beau Brummell by Clyde Fitch. The music score was by Richard Addinsell with Miklós Rózsa. The film stars Stewart Granger as Beau Brummell, Elizabeth Taylor and Peter Ustinov as the Prince of Wales.

The film was made by MGM-British at the company's Elstree Studios. Clyde Fitch's play was written in 1890 as a vehicle for Richard Mansfield. MGM bought the rights in early 1951 as a vehicle for Stewart Granger.