Fans of author Brad Meltzer’s children's books know all too well that Brad has been writing nonfiction for some time with his “ Ordinary People Change the World" series. But now, Brad is out with his first nonfiction book for adults: "The First Conspiracy: The Secret Plot to Kill George Washington." WGBH host Henry Santoro sat down and talked with the New York Times best-selling author. The transcript of the interview below is slightly edited for clarity.

Henry Santoro: The research that you do for your bestselling fiction books, the last of which is "The Escape Artist,” takes you to some amazing places that have amazing facts that you weave into your stories. How, when, and where did you come across a plot to have George Washington killed?

Brad Meltzer: The best stories, especially the real stories, are always found in one place, and it's the footnotes. Almost a decade ago, I was going through the footnotes doing research on George Washington, for one of the thrillers. And I found this footnote that talked about a plot to kill George Washington during the Revolutionary War. And I remember stopping on it. I used it in a book, I put it on one of the thrillers, for like a paragraph, just talking about it. But I couldn’t shake the story.

I said, 'Is this real? Is it nonsense? Is it something you find on the internet?' I remember taking the story toJoseph Ellis, Pulitzer Prize-winning biographer of George Washington. I asked him, 'Do you know this story? Did they really try to kill George Washington?' And he said to me, 'I know the story. I've heard about it.' But, he said, it’s going be hard to tell because by its nature, it’s a story that involves spies.

What happens is, you can find everything about George Washington these days. You can find the number of slaves he owned, you can find when he died, what books he owned. But he said to me, and I’ll never forget, 'You’ll never find the names of all those spies. Their stories by nature are meant to be kept secret forever.' So, by your nature what you're looking for is a ghost.

But he said, 'Look, if you get it, and you find enough, you'll have a book. And if not, you'll have a nice adventure.' Three years later, here we are with the book and we found the true story. There was a plot to kill George Washington, and it was the mayor of New York and the governor of New York plotting to do it, along with Washington's own private security force. When George Washington found out about it, he gathered together 10,000 troops, 10,000 onlookers also came, and built gallows. And 20,000 people watched him hang one of the leaders of the plot against him in the largest public execution at that point in North American history.

Washington brought the hammer down, and said, 'Don't mess with me, I'm George Washington and I’m going to be on the money one day,' right? That's not an actual quote, that's a paraphrase. But all kidding aside, that was the story. And it literally happened on the eve, right after the Declaration of Independence and the British were truly coming. And it was all happening at the same time. I thought, 'I got to write a book about this.' So, “The First Conspiracy” was born. "The Secret Plot to Kill George Washington."

Santoro: And so now the story has surfaced. It sounds like it's so off the charts, that you didn't need a fiction for this book.

Meltzer: Well you know the thing is, if I told my editor, and said, 'Here's the plot I'm going to do. It's going to be a president, and he's going to be the leader of the country. And as the Declaration of Independence, the first draft is being handed in and the country is being invaded, they’re also going to try and kill him. And all this is going to happen at once.' My editor would say, 'No one's going to believe that.' But it happened. And the question is, why do we not know this story?

Santoro: Brad Meltzer’s "The First Conspiracy" is available everywhere. You're going to love it.