Cagney departs from his tough, street smart persona to play the gullible, not so tough Biff Grimes. Notice how he loses fight after fight; in one scene he's a barroom bouncer tossing his drunken father out asking his father not to put up too much of a fight "I'm supposed to be a tough guy".
He gets suckered time after time by Hugo and Virginia. That wouldn't have happened to other Cagney characters! His best scenes are with Olivia DeHavilland. What chemistry. Sometimes no dialog, just glances.
The main characters play off each other phenomenally. Even the minor characters are superb. Who was that fat German who blew beer foam into Cagney's face? He was great! The period music is so woven into the story that the movie almost becomes a musical. The lovely theme that's played whenever Olivia DeHavilland come into the scene is "When You Were Sweet Sixteen". Unlike the title song "Strawberry Blonde", it's never sung in the movie but it was popular at the turn of the century. Perry Como made it one of his hits in the early 1940's.
The movie is such a nostalgic, funny, (sad at times) look back at the turn of the century that you wish you could go back there with them.
It's amazing that director Raoul Walsh also made the brilliant, violent, cynical "White Heat" with nary a sentimental, lovable character.