.... that would be Paul Henreid. Yes, THAT Paul Henreid of "Casablanca" and "Now Voyager" and all things Warner Brothers in the 1940s. But that was then, this is the 1950s.
Our heroine isn't going to be stuck at home with her drunkard father like her "good" older sister, so she sticks out her thumb and heads for a life of crime, small-time at first emptying wallets in a clip joint, but she quickly graduates to grand theft auto and books to the west coast. She joins a gang led by movie tough guy Troy Donahue and becomes part of a caper to rob the local post office of a shipment of diamonds. The gang all get jobs with this federal agency without any identification except their nice white bread faces and busily prepare for the big day. The "good" sister arrives and tries to intervene, but it all goes south and the teenage vermin are dealt with accordingly, probably something minimum-security because of those nice white faces. It's full of bad dialogue and teenage posturing.