The Brit made his debut in the James Bond series in the movie Skyfall (2012). Therein he was introduced as the successor of the ’old’ M, who then was played by Judi Dench. In the last Bond film Spectre (2015) was Fiennes for the first time as the only real M see.
The recordings for the upcoming James Bond film, where Daniel Craig again starring, begin next year. Also other veterans like Ben Whishaw (Q) and Naomi Harris (Eve Moneypenny) back in the jubileumfilm.
Bond 25 is in February 2020 in the United States in the premiere.