Malcolm McDowell was 24 in if.... when he played the character 'Mick Travis'.
That was over 55 years ago in 1968.
This was his first recorded movie acting credit (although may not technically be his first actual acting role).
Today he is 80, and has starred in 214 movies in total, 210 of those since if.... was released.
In if...., I think Malcolm McDowell looks: