If you imagine the most colorful stereotype you can of retro science fiction (minus space battles) you would get pretty close to what this book is. People are frozen to wait for a time when science (and their bank accounts) has improved enough to allow their resurrection. Flying cars whiz between shining buildings where people partake in cafes and malls as beautiful as the Garden of Eden. Food and drink are synthesized for us. There are aspects of the story that seem a bit outdated to the 21st Century reader, such as the air-headed nature of the female lead, but other aspects that send ideas shooting into the future, such as that same woman being identified as a living, breathing individual who cannot be owned by a man, who has sexual autonomy, who can have children with as many different men as she pleases, and who has control of her own income through whatever means she has talent for. Pohl really saw far ahead in the creation of the joymakers, little wands that act as communicators, remote controls, drug dispensers, and internet hookups. (I couldn't help but imagine that they look like the microphones from Mermaid Melody Pichi Pichi Pitch throughout the book!)
The main character is fascinating in that he keeps the reader in the dark for most of the story by purposefully allowing himself to stay in the dark. He does not embrace this new world, ignoring messages and books and other useful information, more curious about the history leading up to his current reality than in the world around him 600 after his birth. The book chronicles his first couple months as a sort of time traveler permanently stuck in the future trying to navigate the bizarre nature of human life when everything has been built to serve them and maintenance is the name of the game.
*SPOILERS*
Charles Forrester wakes up nearly 600 years in the future after becoming one of the first people frozen right before death, revived when technology advanced enough to restore him to health and youth. He finds himself in the vast city of Shoggo among smooth, colorful buildings with flying cars zipping around, giant TV screens, police bots, and handheld devices called joymakers that act as communicators, remote controls, drug dispensers, and more. At first Forrester believes he is rich; his savings from the 1970s have increased in value so that he has a quarter a million dollars. However, after some gratuitous spending, he finds out that the reality is that most of his money was used to bring him back to life (the other half of waiting as an ice cube is waiting for your money to be sufficient to pay for the science) and there are many, many more things to pay for these days: rare foods, joymaker fees, comfortable living, etc. Forrest struggles to shake his 20th Century hangups in order to survive in this new world. He resents the fact that people don't really perform real work anymore, mostly being paid for clubs and hobbies. He also finds interpersonal relationships very confusing, especially as he falls in love with a woman named Adne who he eventually learns has two children by different fathers, neither of whom she was ever married to, and who freely takes birth control and shares her body. He is also confused by everyone's casual treatment of death now that permanent devise is mostly avoidable; people are allowed to fill out paperwork and kill another person legally and he is beaten up due to one such filed license. (There is some suggestion later that permanently dead bodies are cleaned up and added to the Sea of Soup that produces much of the synthetic meat and other foods we have seen Forrester eat throughout the story.) When he realizes that medical and joymaker expenses will soon bankrupt him, Forrester takes the highest paying job readily available and spends his time informing an alien about the history of humanity. The few alien Sirians on the planet are part of a warlike race humanity watches from afar, the ones on Earth kept comfortably captive to prevent them from escaping and bringing the weight of their space fleet upon us. Failing to properly follow instruction, Forrest is fired from that job and starts a tedious job as a system monitor, spending about three hours per day under a dangerously radioactive lake. When he learns of the eventual harm this will do to his body, thus the high pay, he promptly quits, resulting in a surrendered salary and utter bankruptcy. He goes to Adne's children when he joymaker stops working to learn this and they take him to where the Forgotten Men live near the highway. Those who somewhat by choice do not work to maintain a joymaker or other societal comforts spend their time asking for money, drinking much of it away, and reminiscing about the past they left behind when they were frozen. Things change when Forrester witnesses the darker side of humanity as rich people occasionally descend upon the Forgotten Men to kill them for the thrill of ending someone's life permanently. Running as his closest friend is murdered, Forrester is caught by the Sirian he once worked for and hypnotized into helping the alien get back to its ship and take off, leaving him behind. Dazed and confused, he goes to see Adne and her friend Hironubi, who are watching the news. It becomes apparent that the escaped Sirian is on its way home and the imminent destruction of Earth is expected. That being said, the Sirian left most of its substantial Earth wealth to Forrester, making him truly wealthy. No one finds this odd, since the Sirians were always odd. Still, Forrester is overcome with guilt, retreating to his restored apartment for most of a month before emerging to discover that most of the Earth's population has opted to die and be frozen until a future after Sirian destruction arrives. Looking for anyone to talk to, he goes to see Hironubi, who once offered him a job as part of a society that aims to cut technology out of human life. He sees this as a huge opportunity and is working with the remaining Sirians to bring down the system that allows people to live frivolously while machines take care of them. Though Forrester agrees with Hironubi in part, he decides he cannot abide by this potential genocide of the frozen humans. Though the police bots have all been taken over, he has the idea to slice his throat, thus forcing the medical robots to take him to the freezing place to be seen by a human doctor. This works and his throat rapidly heals while the Sirians and Hironubi are taken care of. His part in the Sirian escape is revealed, but outweighed by his saving the human race. Slowly humanity is unfrozen and it is presumed that Forrester continues his journey through future society for many hundreds of years.