This book is the continuation of the book of Charlie and the Chocolate Factory. Willy Wonka has just given the ownership of the whole factory to Charlie. They flew using the Great Glass Elevator to go to Charlie's house. They crashed into the roof of Charlie's house to inform Charlie's family of the good news.
Charlie's grandparents, Grandpa George and Grandma Georgina on his mother's side and Grandpa Josephine on his father's side are nervous of traveling using the elevator. Since they have not got up for 20 years, they refused to get up. So, they were pushed inside on their beds.
The Great Glass Elevator then takes off. During the return trip to the factory, Georgina grabs Wonka away from the controls and strands the elevator with its occupants in Earth's orbit. Wonka sees the chance to link it with the newly-launched Space Hotel, a private enterprise of the US government.
In the white house, the President of the United States and his people see this mysterious object (The Great Glass Elevator) docking at the Space Hotel. They think it contained aliens. The president address Willy Wonka and the others as Martians. Willy Wonka says all kind of nonsense. But then, suddenly, the elevators of the hotel open, and five creatures, brown-green in color shaped like an eggs appear. They change shape and form a word SCRAM. Willy Wonka signaled everyone to get in the elevator and got out of the Space Hotel as quickly as possible. Willy Wonka The things that changed shape were Vermicious Knids, that infested the Space Hotel. They can't get into Earth's surface because of Earth's atmosphere.
The shuttle carrying the chefs and everything was being attacked by the Knids. Charlie suggests that he and his companions use the Elevator to tow the shuttle in to land. Willy Wonka, in agreement, pilots the Elevator into range, wherapon Charlie's Grandpa Joe connects the two vessels by means of a steel cord. This move, however, holds new opportunities for the Knids. Within minutes, they change into living segments of a towing line, with which they intend to drag the spacecrafts away. One large Knid wraps his body around the Elevator, providing an anchor for this operation. Willy Wonka activates the Elevator's retro-rockets and plunges to Earth, taking the shuttle and the Knids with it. The Knids burn to ashes. At the right moment, Wonka releases the shuttle, which floats safely home. The Elevator crashes into the chocolate factory.
Since Charlie was presented the factory as a gift by Wonka, he wants his family to help him run it. But George, Georgina, and Josephine still refuse to move out of their bed. Wonka proposes a pill he invented, Wonka-Vite, to make them young again. However, the three got greedy and take much more than they need to. Instead of becoming a mere twenty years younger, the three grandparents lose eighty years, making George one year old, Josephine three months, and Georgina absent altogether, having become "minus two". Charlie and Wonka make the journey in the Great Glass Elevator to Minusland to get Georgina back with Vita-Wonk, a sprayable compound that makes people older. Minusland is a dark, gloomy region far beneath the surface of the Earth, filled up entirely with fog, and inhabited only by the invisible and highly dangerous Gnoolies, creatures which, with a single bite, turn their victims into more Gnoolies. After administering an even worse overdose of Vita-Wonk to Grandma Georgina, they return to the upper world. Georgina has become centuries old. Using a more cautious dose of Wonka-Vite, her companions subtract much of this age from her, leaving her at seventy-eight as she was before. Turning to George and Josephine, Charlie and Mr. Wonka administer Vita-Wonk enough to recall their original age.
The grandparents, finally restored to their proper ages, are still incensed with Wonka's adventurous nature. They refuse, as before, to come out of bed. The Oompa-Loompas then come in and give Wonka a letter from the President, congratulating the occupants of the Great Glass Elevator on saving the lives of the shuttle astronauts and hotel staff and inviting them as the guests of honour to a White House dinner. The grandparents don't want to be left out, so they leap out of bed and join Charlie, Grandpa Joe, Wonka, and Charlie's parents to enter the helicopter sent to pick them up.
This book is as good as Charlie and the Chocolate Factory. I give this book a 9/10 rating also...