John Cleese was 61 in Harry Potter and the Philosopher's Stone when he played the character 'Nearly Headless Nick (Sir Nicholas)'.
That was over 23 years ago in 2001.
Today he is 84, and has starred in 161 movies in total, 78 of those since Harry Potter and the Philosopher's Stone was released.
In Harry Potter and the Philosopher's Stone, I think John Cleese looks: