Andy Serkis was 38 in The Lord of the Rings: The Return of the King when he played the character 'Gollum / Sméagol'.
That was over 20 years ago in 2003.
Today he is 59, and has starred in 75 movies in total, 51 of those since The Lord of the Rings: The Return of the King was released.
In The Lord of the Rings: The Return of the King, I think Andy Serkis looks: