I found this drama genius. It's full of cropped up anger, for one, just as the title suggests.
Jimmy, the "anti-hero" of the play, is the one who is angry. Angry at everything and everyone. Or almost everyone, he seems to care a lot for those who have suffered, just like he has.
He can't stand the "posh" and aristocratic members of society, those with a seemingly easy life. Those who have money should never complain, he thinks. He is married to someone of that group he hates so much, and although he loves her personally, he takes out all his anger on her. Not very fair, because I don't think the poor girl ever wronged him.
I could go on and on describing how it's brilliantly woven into a story full of bitterness, hurt, confusion, and love, but you'd be missing out on a lot if you don't just read it.