We’ve been waiting for the publication of Harper Lee’s new novel “Go Set a Watchman” ever since it was discovered earlier this year. Now, on the eve of the book’s release, details have emerged on the major plot points. Spoiler alert.

Here is the Covered Bridge list of five things you should know about “Go Set A Watchman” before you decide to pick it up.

1. It’s not a new novel, it’s an old one.

Though “Watchman” is being published for the first time now, it was essentially an early version of “Mockingbird.” According to news accounts, “Watchman” was submitted to publishers in the summer of 1957; after her editor asked for a rewrite focusing on Scout’s girlhood two decades earlier, Ms. Lee spent some two years reworking the story, which became “Mockingbird.”

2. It was discovered by Harper Lee’s Attorney.

“I was so stunned. At the time, I didn’t know if it was finished,” Ms. Carter recalled in an interview on Saturday, her first extensive comments about the discovery. She went to see Ms. Lee and asked her if the novel was complete. “She said: ‘Complete? I guess so. It was the parent of “Mockingbird.” ’ ”

3. The novel is set in Maycomb, many years after To Kill a Mockingbird.

While written in the third person, “Watchman” reflects a grown-up Scout’s point of view: The novel is the story of how she returns home to Maycomb, Ala., for a visit — from New York City, where she has been living —

4. Atticus Finch is…different. 

Shockingly, in Ms. Lee’s long-awaited novel, “Go Set a Watchman” (due out Tuesday), Atticus is a racist who once attended a Klan meeting, who says things like “The Negroes down here are still in their childhood as a people.” Or asks his daughter: “Do you want Negroes by the carload in our schools and churches and theaters? Do you want them in our world?”

5. There may be a third ‘Scout’ novel. 

What of the other pages that have for decades sat in the [safety deposit box] on top of “Watchman”? Was it an earlier draft of “Watchman,” or of “Mockingbird,” or even, as early correspondence indicates it might be, a third book bridging the two? I don’t know. But this much I do know: In the coming months, experts, at [Lee’s] direction, will be invited to examine and authenticate all the documents in the safe-deposit box.

The revelations about the changes to Atticus Finch have shocked and roiled fans of America’s most loved novel. But some say it may not be such a bad thing. Read more over at the New York Times. You can also read the first chapter of the book at the Wall Street Journal.