Desmond Llewelyn (12 September 1914 – 19 December 1999) was the most famous actor to portray Q. He acted in the role from From Russia with Love to The World Is Not Enough except Live and Let Die. He also reprised the role in a 1967 TV feature, Welcome to Japan, Mr. Bond, alongside Lois Maxwell.
Desmond Llewelyn died in a car accident after coming home from a book signing in 1999. His role was replaced by John Cleese, who had previously played R, in 2002's Die Another Day. Having appeared in 17 of the 18 James Bond films released between 1963 and 1999, he had appeared in more James Bond films than any other actor.