Paul Reiser was 24 in Diner when he played the character 'Modell'.
That was over 42 years ago in 1982.
This was his first recorded movie acting credit (although may not technically be his first actual acting role).
Today he is 67, and has starred in 46 movies in total, 44 of those since Diner was released.
In Diner, I think Paul Reiser looks: