Warren Beatty was 19 in The Night America Trembled when he played an uncredited character.
That was over 67 years ago in 1957.
This was his first recorded movie acting credit (although may not technically be his first actual acting role).
Today he is 87, and has starred in 45 movies in total, 45 of those since The Night America Trembled was released.
In The Night America Trembled, I think Warren Beatty looks: