

That was over 20 years ago in 2002.
Today he is 77, and has starred in 31 movies in total, 10 since Star Wars: Episode II - Attack of the Clones was released.
In Star Wars: Episode II - Attack of the Clones, I think Ian McDiarmid looks:
Star Wars: Episode II - Attack of the Clones scores 6.4 out of 10 on The Movie Database.
Ian McDiarmid's first acting role was as 'Senator Palpatine' in Star Wars: Episode I - The Phantom Menace, released in 1999 when he was 54.