George's Secret Key to the Universe

George’s Secret Key to the Universe (2007) is a middle-grade novel by author Lucy Hawking and physicist Stephen Hawking. The novel introduces young readers to astronomy and physics through the story of George Greenby, a curious boy who befriends a scientist and embarks on a cosmic journey. The first in a six-book series, George’s Secret Key to the Universe has been praised for making science accessible to children while exploring themes of The Ethical Use of Knowledge and Technology, The Importance of Science and Stewardship of the Earth, and The Struggle to Be Understood.

This guide uses the eBook version of George’s Secret Key to the Universe, written by Lucy and Stephen Hawking, with contributions from Christophe Galfard and illustrator Garry Parsons, and published by Simon & Schuster Books for Young Readers.

Content Warning: The source material and guide feature depictions of bullying and physical assault.

Plot Summary

George is a curious and imaginative boy whose deep interest in science often clashes with his parents’ rejection of modern technology. George’s parents live by strict environmental ideals: They grow their own food, avoid machines, and emphasize living a “simpler life.” They hope to protect George from the dangers of modern inventions, but their philosophy leaves him feeling isolated and frustrated. His only companion is his pet pig, Freddy, a Christmas gift from his grandmother. One day, George discovers that Freddy has escaped from his sty, most likely because George forgot to latch the gate.

While searching for Freddy, George realizes that the pig has wandered through a broken fence into the neighboring property—an overgrown and forbidden place called Next Door. The house was abandoned after its elderly owner mysteriously disappeared. Despite his parents’ warnings to stay away, George sneaks through the fence to retrieve Freddy. Inside the house, he finds the pig happily drinking a bowl of grape soda, and he meets a girl named Annie and her father Eric.

Eric and Annie have recently moved to the neighborhood. Unlike George’s parents, Eric is a scientist who embraces technology. When George’s curiosity about their house grows, Eric reveals a remarkable computer named Cosmos. Cosmos introduces himself as the most advanced computer in the world. Through a portal Cosmos creates, Eric shows George a simulation of the birth and death of stars. However, before Cosmos can begin, George must take The Oath of the Scientist, promising to use knowledge only for the good of humanity and never for selfish or destructive purposes. He also promises to keep Cosmos a secret. Through Eric’s explanations and Cosmo’s presentations, George learns how stars form through nuclear fusion, how planets take shape from the debris of stellar explosions, and how the elements necessary for life were created inside stars.

At school, George has a strict science teacher named Dr. Reeper—nicknamed “Greeper” by students—who frightens him and the other children. When Dr. Reeper notices George daydreaming in class, George blurts out the secret about Cosmos, accidentally breaking his promise. Reeper’s reaction is suspiciously intense, and he assigns the class one hundred lines before they can leave.

Outside of school, George is harassed by Ringo—the class bully—and his band of friends: Zit, Whippet, and Tank. George tries to escape, but they follow him home, where he finds himself locked out of the house. Dressed in a space suit, Annie comes out from Next Door, scaring the boys away and bringing George inside.

There, she insists on proving Cosmos can open a real portal to space. Despite Cosmos’s protests, Annie activates the portal, and she and George leap out onto a comet orbiting through the Solar System. George experiences weightlessness and watches Saturn’s rings, pocketing a space rock as a souvenir. Their adventure turns dangerous after the comet passes near Jupiter and then through an asteroid field. Annie’s antenna breaks, leaving her unable to reach Cosmos or speak to George. Eric and Cosmos eventually save them. Furious, Eric grounds Annie and takes George home, where George, too, is grounded for a month. Eric says he will keep Cosmos locked away from the children for their safety.

During their punishment, George reflects on what he learned and begins to miss Annie. He notices a poster advertising a science competition, with a computer as the grand prize. Excited, he decides to enter but struggles to choose a topic. Near the end of their punishment, Annie and George secretly meet, hiding in Freddy’s shed. Annie says her father won’t let her travel in space again until she is an adult. She also says her mother, Susan, is away helping her ill grandmother. She encourages George to focus his project on space, suggesting that Eric could help make sure his presentation is accurate. George’s mother catches them, but she only brings them snacks.

After disrupting George’s father’s speech and a climate protest, Ringo and his friends roam the town playing pranks. They wind up at Dr. Reeper’s house and are invited inside to see his scientific experiments. Dr. Reeper claims to be recreating the conditions that once existed on early Earth by combining volcanic gases and lightning to form amino acids, which he describes as the “building blocks of life” (162). He gives Ringo a letter to deliver to Eric, claiming it contains information about a newly discovered planet.

When George later visits Eric’s house to prepare for the competition, Eric invites him to listen to a conference. He is invited to participate at the end by answering whether humanity should protect the environment on Earth or search for a new planet. He suggests humanity should do both, and Eric agrees. While helping Eric clean after the conference, George finds the letter from Dr. Reeper, finding the handwriting familiar but not quite recognizing it. Believing the letter to be genuine, Eric excitedly opens the portal and passes through, disappearing into space. Too late, George realizes the handwriting belongs to Dr. Reeper, and he suspects the letter is a trap. He uses Cosmos to find Eric and, donning a space suit, joins him on an asteroid. While trying to send George back, Eric gets pulled toward a black hole.

Landing alone in Eric’s library, George finds Cosmos missing. Looking outside, he sees Ringo’s gang fleeing down the street, arguing with Cosmos. Unable to reach them, George goes back inside to look for the book about black holes that Eric had told him to find before the portal separated them. He finds it and returns home, but when he goes to read it, he becomes frustrated, unable to understand the material. His mom comes to check on him, picking up the book and dropping a smaller book within—a simplified version of the text Eric wrote for Annie and George. Reading it, George learns that black holes eventually emit everything that goes into them, meaning they can save Eric.

The next day is the science competition. George first goes to Dr. Reeper’s house, where the teacher is attempting to break into Cosmos. Rushing to school, he finds Annie, then shouts to the teacher that he wants to change his topic to discuss Cosmos. He sees Ringo make a phone call. Shortly after, Dr. Reeper arrives at the school and is enlisted to sit as a judge. George and Annie escape the school through a window in the coatroom, then Annie calls her mother, who drives them to Dr. Reeper’s house. The children tell Susan what has happened, and Susan talks vaguely about her and Eric’s history with Dr. Reeper.

With Susan’s help, they successfully enter Dr. Reeper’s house and find Cosmos. Exhausted, Cosmos asks to be plugged back in, then asks for the information about black holes, which has not yet been uploaded into his system. Once the text is uploaded, he is able to open the portal, speed time, and “filter” Eric’s particles from the rest, reconstructing him, though with the wrong glasses.

They return to the science competition, where George is just in time to give his speech. He explains what he has learned about space and science and stresses that scientific knowledge must be used responsibly and for the benefit of humanity. Dr. Reeper is upset with the topic change but quiets down when he sees Eric in the crowd.

George wins first place in the competition, receiving the computer. His father—who, to George’s surprise, has attended the competition—agrees to let George keep the computer but with limits. Eric expands on his relationship with Dr. Reeper. They had once worked together under the same tutor—the man who had lived Next Door and disappeared. However, both Eric and Susan refuse to share specific details about what happened.

The novel concludes with both families sharing dinner together. George’s father and Eric discuss humanity’s next steps, while Annie feeds Freddy. Afterwards, George falls asleep while thinking about space.