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Charlie Thorne and the Last Equation


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About The Book

“Fast-paced, smart, and action-packed...a real page-burner.” —Chris Grabenstein, #1 New York Times bestselling author of the Mr. Lemoncello’s Library series

From New York Times bestselling author Stuart Gibbs comes the first novel in a thrilling new series about the world’s youngest and smartest genius who’s forced to use her unbelievable code-breaking skills to outsmart Einstein.

Charlie Thorne is a genius.
Charlie Thorne is a thief.
Charlie Thorne isn’t old enough to drive.

And now it’s up to her to save the world…

Decades ago, Albert Einstein devised an equation that could benefit all life on earth—or destroy it. Fearing what would happen if the equation fell into the wrong hands, he hid it.

But now, a diabolical group known as the Furies are closing in on its location. In desperation, a team of CIA agents drags Charlie into the hunt, needing her brilliance to find it first—even though this means placing her life in grave danger.

In a breakneck adventure that spans the globe, Charlie must crack a complex code created by Einstein himself, struggle to survive in a world where no one can be trusted, and fight to keep the last equation safe once and for all.


Charlie Thorne and the Last Equation ONE
CIA headquarters

Langley, Virginia

Present day

The director of the Central Intelligence Agency scrutinized the photograph of Charlie Thorne, then dropped it on the conference table and gave Agent Dante Garcia a hard stare. “You must be joking.”

“I’m not,” Dante replied solemnly.

“This is a twelve-year-old girl!” Director Carter exclaimed.

“She’s not a normal twelve-year-old.”

“I don’t care if she can fly,” Carter snapped. “I own pairs of shoes that are older than this kid. The fate of humanity is at stake here and you want me to rely on someone who’s barely a teenager?”

“Desperate times call for desperate measures,” Dante said.

“These measures aren’t desperate. They’re insane.”

“Well, maybe it’s time we tried something crazy. The CIA has been using the same old techniques to find Pandora for almost seventy years, and they haven’t gotten us anywhere. They certainly didn’t work in Bern.”

Director Carter’s gaze went cold, making Dante think that he’d pushed things too far. But then Carter gave a slight nod, conceding that he was right, and sat back in her chair to think.

Dante had seen the director lapse into deep thought before, though never when he was the only one in the room with her. The previous times, he had been a junior agent, relegated to the background, expected only to observe and keep his mouth shut. Carter’s long pauses to think in meetings were legendary at the Agency. She had been known to not say anything for up to ten minutes, during which she expected complete silence. This could be awkward for the other agents in the room, but they all greatly respected Carter—revered her even—and so they dealt with it.

Jamilla Carter was in her sixties, the rare CIA director who had risen to the job by being an exceptional agent rather than a political appointee. Her piercing brown eyes stood out against her dark skin. She had been an analyst, rather than a field operative, but then, most CIA employees were analysts, and Carter was one of the best.

Carter was in analysis mode now. She picked up the file Dante had assembled on Charlie Thorne and leafed through it for what was probably the twentieth time that day.

Dante grew uncomfortable watching her, so he let his gaze drift out the window. It was January and the sky was roofed with gray clouds. Squalls of snowflakes swirled outside the window. Even on a sunny day, the buildings of CIA headquarters were drab; today they looked ominous and foreboding.

Carter’s eyes shifted from the file to the photograph once again.

Charlotte Thorne, aka Charlie, was a mix of many different races, although she didn’t look like one more than any other. If Charlie had been ten years older, this would have been a huge asset. She could have passed for a very tan white person, a light-skinned black person, or Hispanic or Arab or Indian, or even partly Chinese. Looks like that would allow you to blend in anywhere on earth, to pass yourself off as almost any culture if you could speak the language.

But Dante hadn’t suggested Charlie because of her appearance. It was because of her intelligence. Her IQ was off the charts. Director Carter had dozens of certified geniuses under her at the CIA, and none of them had IQs as high as Charlie Thorne’s. Carter wouldn’t have believed anyone could score that high if Dante hadn’t provided three separate reports from respected psychologists to confirm it.

Carter flipped through the psych reports again. She had read them twice already. The second time, she had marked them with a red pen, circling words or phrases that were important to her, for reasons that were good or bad. Finally, she looked back at Dante.

“She’s brilliant,” Carter said. “I’ll give you that.”

“She’s beyond brilliant,” Dante corrected. “She speaks at least twelve languages and can understand more. She’s already been accepted to college, studying advanced math and theoretical physics. She has a photographic memory. . . .”

“There’s no such thing as a photographic memory.”

“Well, hers is as close as it gets. Her mind is wired differently than ours. She knows everything about everything. Science, history, art . . . you name it.”

“Perhaps. But there are other characteristics of her personality that are more worrisome.” Carter tapped some of the reports where she had made notes. “Rebellious. Headstrong. Conceited. Disrespectful of authority.”

“Do you know who else was like that as a child?” Dante asked. “Albert Einstein. As well as Leonardo da Vinci, Isaac Newton, Charles Darwin, Benjamin Franklin, and every other groundbreaking genius you can name. Anyone that brilliant is going to chafe at authority. Because they’re smarter than the authorities.” Dante leaned across the conference table. “The CIA has been searching for Pandora ever since Einstein died, and we’ve gotten nowhere. So maybe we need someone as smart as Einstein to find it. And the closest person we have to Einstein right now is her.” Dante thumped his finger on the photo of Charlie Thorne.

Carter’s eyes fell to the photo again, then returned to Dante. Agent Garcia was mentally gifted himself; that was why Director Carter was even sitting here with him, considering his radical suggestion, when she had a thousand other things to do. Like dealing with the fallout from Bern.

Dante was only twenty-eight, but he had already proved himself in the field many times, rising rapidly through the ranks. Like Charlie Thorne, he was a blend of races, able to pass as almost any ethnicity he wanted, meaning he had served all over the world.

“Miss Thorne’s disrespect for authority probably goes much farther than Einstein’s ever did,” Director Carter said. “As far as we know, Einstein never broke the law, whereas Miss Thorne has. And in rather spectacular fashion.”

“That’s exactly why she’ll work for us.”

Carter arched an eyebrow. “You want to blackmail her into helping us? That’s not exactly going to make her respectful of authority.”

“I can handle her.”

Carter leafed through the file on Charlie Thorne one last time, considering all the possible ramifications of bringing this girl aboard. The kid was a risky play, for sure. The chances were high that it wouldn’t work. And yet, as Agent Garcia had said, these were desperate times. Carter’s intelligence said the Furies were closing in on Pandora; meanwhile the CIA was no closer than it had been seven decades ago.

“This will have to be an unsanctioned mission,” Carter said. “Completely off the books. There can’t be any record that the CIA is coercing twelve-year-olds to work for us.”

Dante smiled. “Of course not.”

“That means a bare-bones operation as well. Only you and one other agent.”

Dante’s smile faded. “Only one other? That’s crazy!”

“Weren’t you just telling me it was time to try something crazy? If it helps, you can select whoever you want.”

Dante didn’t hesitate for a second. “Milana Moon.”

Director Carter nodded. Even though she had thousands of agents working under her, she knew exactly who Moon was. The fact that Dante had named her so quickly simply confirmed his intelligence to her. “Fine. If she’ll agree to it.”

“I think I can convince her.”

“Then we’re done here.” Carter snapped to her feet and slid the file back across the conference table to Dante. “Destroy that. And then go find Pandora.”

About The Author

Photograph by Dashiell Gibbs

Stuart Gibbs is the New York Times bestselling author of the Charlie Thorne series, FunJungle series, Moon Base Alpha series, Once Upon a Tim series, and Spy School series. He has written screenplays, worked on a whole bunch of animated films, developed TV shows, been a newspaper columnist, and researched capybaras (the world’s largest rodents). Stuart lives with his family in Los Angeles. You can learn more about what he’s up to at

Product Details

  • Publisher: Simon & Schuster Books for Young Readers (September 1, 2020)
  • Length: 416 pages
  • ISBN13: 9781534424777
  • Ages: 10 - 99

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Raves and Reviews

2019 Parents' Choice Recommende Seal award winner

"Stuart Gibbs’s CHARLIE THORNE AND THE LAST EQUATION is fast-paced, smart, and action-packed. Gibbs knows how to write a real page-burner. Charlie Thorne is a younger, smarter, cooler version of Jason Bourne."

– Chris Grabenstein, #1 New York Times bestselling author

"Whether she’s catching big air on her snowboard or deciphering clues hidden by Albert Einstein, Charlie Thorne is an ideal hero for a new generation. Her pulse pounding adventure unfolds like one of the equations she’s so skilled at solving – the final answer remains concealed until every last variable has been uncovered."

– James Ponti, Edgar-award winning author of the Framed! and City Spies series

"Action-packed and thrilling."

– School Library Connection, recommended

"Charlie is a terrific hero—outrageously smart, courageous, and still believable as a kid. After this explosive start, young readers will eagerly await her next adventure."

– Publishers Weekly

"Gibbs deftly pens an Alex Rider–level adventure with this series starter…It doesn’t take a theoretical physicist to predict that this series will be popular."

– Booklist

Awards and Honors

  • Kentucky Bluegrass Award Master List
  • Grand Canyon Reader Award Nominee (AZ)
  • Pennsylvania Young Reader's Choice Award Master List
  • Maine Student Book Award Reading List
  • Nutmeg Book Award Nominee (CT)
  • Great Stone Face Book Award Nominee (NH)
  • Texas Lone Star Reading List
  • Black-Eyed Susan Book Award Nominee (MD)
  • Mark Twain Award Final Nominee (MO)
  • Iowa Children's Choice Award
  • Lectio Book Award Finalist (TX)
  • Sunshine State Young Readers Award, Grades 6-8 List (FL)
  • Vermont Middle-Grade Children's Book Award
  • Cartwheel Book Awards Nominee

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