Philip Roth's American Trilogy shows many of the gritty realities of American life, using different people in different periods of time. A once-popular high school athlete whose daughter may be a domestic terrorist, beautiful lives destroyed during the McCarthy era, a former college professor with skeletons in the closet.. all of these show Roth's creativity and ability to create a startling portrait of American life. Roth's signature character and alter-ego Nathan Zuckerman is here, but only on the sidelines; he is the narrator.
The former humor of Roth is mostly gone; it hasn't been seen since Operation Shylock. The novels are still funny, albeit in a very black way, but it isn't the same. They are instead mostly serious, dark meditations on the reality of the American dream.
None of these novels are Roth's best (I would give that to The Counterlife) but they are all very good. One by one:
American Pastoral: This is the first novel of the series and seems to be most people's favorite of the bunch. For many people, it is their favorite Roth novel period. It is strange, then, that this is probably my least favorite of the bunch. It has an excellent story and character development, but falls a bit flat towards the end. Despite that, it is a scary, sad, gritty and occasionally funny novel.
I Married a Communist: And now, the second novel in the series, I Married a Communist. Another surprise; this seems to be most people's least favorite of the three, but it is my favorite. I can see why people wouldn't like it (Saul Bellow, long time friend and admirer of Philip Roth, hated this novel) but I found it to be scary and real. Read it and tremble.
The Human Stain: The Human Stain, the last novel of the three, is an incredibly sad, though oddly moving novel. I like it nearly as well as I Married a Communist, in some ways more. Reading about Coleman Silk's tragic plight is difficult but rewarding. The movie of the same name is decent, but nothing like the novel.
I don't like to extensively review novels, because you would be much happier just reading them for yourself. However, I would not say to start with any of these novels if you're new to Roth. Go with his first novel, Goodbye Columbus, which is also one of his best. You will see just how amazing he is, and can work your way up from there.