There's fucking spoilers, *obviously*.
So I read To Kill A Mockingbird for the first time when I was eight. It was in a Reader's Digest Condensed Book (are those even made anymore?) and being a white girl raised in a Northern town where the only black people I ever saw were Lt. Uhura on Star Trek and Elizabeth on The Tomorrow People, my initial takeaway from the book was that I didn't really get why everyone was allowed to say the n word out loud and Scout was pretty kickass. I mostly thought it was kinda creepy that there was a shut in neighbor. I read it again when I was fourteen, and frankly I read it the way you'd expect a teenage girl raised in an oddly liberal upstate NY town - I was full of indignant anger over how racist and stupid Southerners were (my dad came here from England but my mom's people were proud Irish micks who served on the side of the Union) and of course, some smug attitude about how much cooler we were about things in my part of the world.
As I got older I would go back to it, because it's a nuanced story and there's always new things, and frankly because my own life experiences are no longer so narrow and I can now see how childish or simply arrogant my own views were. Obviously, racism isn't just a southern thing (although really, the South does test my patience often) obviously things aren't ok, but this book always exemplified a certain hope of mine, that good people will at least try to do what is right. Really, Atticus Finch is the kind of person you want to be when you grow up.
And Scout was pretty badass. And To Kill A Mocking Bird is a beautifully written book that deserves its status as A Great American Novel.
With my bias and affection stated...
I'm going to talk about it first as a book by itself, because its meant to be read on its own.
It's not very good or very engaging. There's not a lot of action. It's Jean-Louise aka Scout, now an adult, returning home to visit her father Atticus, her Uncle Jack, her childhood friend Hank and her Aunt Alexandra. If I didn't know Maycomb, seeing it through Jean-Louise's eyes would have little impact. Yes, she's disillusioned to realize her dad, who once got a black man acquitted on a rape charge (ahem more on that later) has apparently been a member of the KKK and various citizen's councils for years. Yes, she's disillusioned to find out that Calpurnia the black maid who raised her like a daughter didn't really love her like a daughter. Yes, she's disillusioned to finally realize her aunt hates the idea of her marrying Hank because Hank is jumped up white trash. Yes, she's disillusioned to find out Hank is totally on board with stopping the NAACP from seeking justice for black people.... Frankly it's like Jean-Louise just realized she was raised in Alabama.
Hank is a new character and he's a young lawyer who is Atticus's protégé, and is from a white trash family. He was friends with Jem, Jean-Louise's brother who is dead by the way. Not that it matters, because Jem in Go Set A Watchman is a poorly drawn cipher. There's some lengthy reminiscing, not about anything you might expect, and about halfway through the book, Jean-Louise realizes Atticus and Hank are about to merrily railroad Calpurnia's grandson to prison for a hit and run sort of thing because basically, they don't want to have black people be equal.
The second half of the book is Jean-Louise yelling at people and explaining how she's color blind and how she can't believe her daddy isn't the perfect man she thought and everyone, including Atticus, acting like she really needs to clear her head and get with the program. It's mostly a lecture on how racism is bad and to be fair, that there are some reasons why southerners are racist that aren't simple or easy to wave away... but there's also next to no resolution at the end. It's dull. You will get to the end and think "but was there a plot?"
The answer is no, there wasn't.
Now, as a sequel/prequel to To Kill A Mocking Bird....
First, quite frankly, I seriously question whether this was ever intended for publication. It reads like a first draft. It has factual things from TKAMB wrong - Tom Robinson wasn't acquitted, he was killed in prison after being convicted for rape. Dill is mentioned slightly in Go Set A Watchman and Hank isn't mentioned in TKAMB AT ALL despite living across the street and being Jem's constant companion. There's no mention of Boo Radley at all.
Second... the folks who watch BSG will get this. When Atticus is revealed to be a racist... it's like when Ellen Tigh was revealed as the final Cylon. It has awesome shock value, and I can even argue it's a valid place to go. After all, Atticus in TKAMB wanted to make sure Tom Robinson was treated fairly and given a fair trial under the law. That doesn't necessarily indicate that Atticus's concern was due to his lack of racism, it could have been his love of the law and fairness. However...
One of the most powerful moments in Battlestar Galactica is when Saul kills Ellen. He doesn't want to, but he has to, and she knows it and it's a brilliantly illuminating moment. But once you know Ellen comes back to life and walks off hand in hand with Saul at the end... you can't see the bitter agony of the Tighs again.
Now, is To Go Set A Watchman that ruining? No, because frankly, its a pretty shitty book. But there is that moment of shock where you're all "No, no, Atticus, not you".
And then you pop the movie in and watch Gregory Peck restore your faith that yes, good people like Atticus Finch do stand up for what's right.