Boston ? Brad Meltzer received two pieces of correspondence at just about the same time three years ago.

The first was a letter from former President George H.W. Bush saying he enjoyed reading Meltzer’s book, “The Millionaires.”

The second, sent by a friend, was a list of some of history’s most famous Freemasons.

Together, they provided the inspiration for Meltzer’s sixth novel, “The Book of Fate,” which went to No. 1 on The New York Times list of best-sellers last month and remains at the top of best-seller lists.

Meltzer asked to meet the former president and spent nearly a week with George and Barbara Bush in Houston, where he had almost unlimited access to their daily lives. He also spent time at Bill Clinton’s New York offices, which, combined with Bush, gave him a remarkable view into the lives of former presidents.

Both men, he found, experienced an emptiness in their lives having gone from “the most powerful man in the world one day, to the next day a guy who has to stop at red lights like the rest of us,” he said during a visit to Boston to promote his new thriller, “The Book of Fate.”

Author Brad Meltzer signs books after a reading from his latest title, The

“I think Bush and Clinton both left the White House with the same level of depression,” said Meltzer, who sprinkled true anecdotes about former presidents throughout the book. “The loss of power is absolute.”

New ground

Meltzer, 36, also became fascinated by the Freemasons, a secret fraternal organization founded in the middle ages that has been the subject of conspiracy theories throughout history, but today is engaged in charitable and civic work.

“I had no idea what a Freemason was. I had no idea it was the world’s oldest fraternity. I knew nothing about it,” he said. “Voltaire, George Washington, Winston Churchill, Bob Dole, Jesse Jackson, John Wayne, Harry Houdini and 15 U.S. presidents were Freemasons. I just became obsessed.”

He learned that landmark buildings in Washington, D.C., are decorated with Freemason symbols and that city streets are laid out to represent Freemasonry’s most sacred symbols, the compass and square, and the five-pointed star.

The book’s main character, Wes Holloway, moves in this world of former presidents and Freemasonry, betrayed by those he trusts most and pursued by a trio of rogue federal agents and a psychopathic killer driven by voices in his head. To save himself, and figure out why a colleague he thought had been killed eight years ago during an apparent assassination attempt on the president is very much alive, he must crack a 200-year-old Freemasons code.

Compelling characters

Meltzer bristles slightly when “The Book of Fate” is referred to as a “political thriller” or a “conspiracy theory” novel.

To him, the genre of his books is unimportant. The plot is not important. It’s the characters. He calls Holloway the most complex character he’s ever written.

“If I have a good character, you’ll follow that character for 500 pages. But if I don’t have a good character and I have the greatest plot in the world, you won’t follow that character for 20 pages,” he said.

In the first chapter, Holloway is self-assured and arrogant, in his early 20s and already in the president’s inner circle, his future unlimited. In chapter 2, eight years later, he is insecure, a broken man having suffered severe nerve damage and permanent scars on his face after taking bullet fragments in the cheek during the assassination attempt. As his name suggests, he is a hollow version of his former self.

Holloway is also very personal, based partly on Meltzer’s father, whose forehead was severely scarred following surgery to remove a cancerous growth.

“I just didn’t want to sit down and write the main character of every cheesy thriller that’s out there,” Meltzer said. “So I said, ‘What if I take that character and wreck him in the first chapter?’ He’s the opposite of every hero in every thriller on purpose.”