Jack Palance was 30 in Panic in the Streets when he played the character 'Blackie'.
That was over 74 years ago in 1950.
This was his first recorded movie acting credit (although may not technically be his first actual acting role).
In 2006 he died aged 87, starring in 119 films in his career, 118 of those after Panic in the Streets was first released. If he were alive today he would be 105.
In Panic in the Streets, I think Jack Palance looks: