Aidan Gillen was 18 in The Lonely Passion of Judith Hearne when he played the character 'Youth at Liquor Store (as Aiden Murphy)'.
That was over 35 years ago in 1987.
This was his first recorded movie acting credit (although may not technically be his first actual acting role).
Today he is 55, and has starred in 62 movies in total, 58 of those since The Lonely Passion of Judith Hearne was released.
In The Lonely Passion of Judith Hearne, I think Aidan Gillen looks: