The action takes place at the end of the 20th century. in the city of Harmont, which is located near one of the Visitation Zones.

The Visiting Zone - there are only six of them on Earth - this is the place where, several years before the events described, space aliens landed for several hours, leaving numerous material traces of their stay. The zone is fenced and carefully guarded, the entrance to the Zone is allowed only by passes and only to employees of the International Institute of Extraterrestrial Cultures. However, desperate guys - they are called stalkers - penetrate the Zone, take out everything they can find from there, and sell these unearthly wonders to the buyers, each of which has its own name for stalkers - by analogy with earthly objects: “pin”, “dummy” , “Itching”, “carbonated clay”, “black spray”, etc. Scientists have several hypotheses about the origin of the Visitation Zones: perhaps some extraterrestrial mind threw containers with samples of its material culture onto the Earth; perhaps the aliens still live in the Zones and are closely studying earthlings; or perhaps the aliens stopped on the Earth on the way to some unknown cosmic target, and the Zone is like a picnic on the side of the cosmic road, and all these mysterious objects in it are simply thrown or lost things scattered in a mess, as after an ordinary, terrestrial a picnic in the clearing remains traces of a fire, apple bits, candy wrappers, tin cans, coins, spots of gasoline and the like.

Redrick Schuhart, a former stalker, and now an employee of the Institute for Extraterrestrial Cultures, works as a laboratory assistant for the young Russian scientist Kirill Panov, who is engaged in the study of one of the mysterious objects found in the Zone - “dummies”. “Dummy” is two copper discs the size of a tea saucer, between which there are forty centimeters apart, but it is neither possible to press them against each other, nor to separate them. Red, who really likes Cyril, wants to make him happy and offers to go to the Zone for a complete “dummy” that has “something blue inside” - he saw this during his stalker trips to the Zone. Wearing special costumes, they go to the Zone, and there, by chance, Cyril touches some strange silver web with his back. Red is worried, but nothing happens. They return safely from the Zone, but after a few hours Cyril dies of a heart attack. Red believes that he is to blame for this death - he overlooked the web: there are no trifles in the Zone, any trifle can be a mortal danger, and he, a former stalker, knows this very well.

A few years later, Redrick Schuhart, who quit the Institute after Cyril's death, again becomes a stalker. He is married, and his daughter Maria is growing - the Monkey, as he and his wife Guta call her. The children of stalkers are different from other children, and the Monkey is no exception; her face and body are covered with thick long hair, but otherwise she is an ordinary child: she is naughty, chatting, likes to play with children, and they love her too.

Redrick travels to the Zone with a partner nicknamed Vulture Barbridge, so nicknamed for his cruelty to fellow stalkers. Barbridge cannot go back, because his legs hurt him: he stepped into the “witch’s jelly”, and his legs became like rubber beneath his knees — you could tie a knot. The vulture asks Red not to leave him, promising to tell where in the Zone lies the Golden Ball, fulfilling all wishes. Shekhart doesn’t believe him, considering the Golden Ball an invention of superstitious stalkers, but Barbridge claims that the Golden Ball exists and has already received a lot from him, for example, he, unlike other stalkers, has two normal and, moreover, remarkably beautiful children - Dina and Arthur. Red, who did not believe in the existence of the Golden Ball, nevertheless removes Barbridge from the Zone and takes him to a doctor - a specialist in diseases caused by the influence of the Zone. However, Barbridge could not be saved. Having set off on the same day with prey to buyers, Red is ambushed, he is arrested and sentenced to several years in prison.

After serving his time and going free, he finds his daughter so changed that doctors say that she is no longer a man. Not only has she changed outwardly - she already understands almost nothing. To save his daughter, Red goes to the Golden Ball: Barbridge, remembering that Red did not throw him in the Zone, gives him a map, explains how to find the ball, and wants Red to ask him to return his legs: “The Zone took, maybe Zone and will return. " On the way to the ball, you need to overcome many obstacles that the Zone is full of, but the worst thing is the "meat grinder": one person must be sacrificed to her so that the other can go to the Golden Ball and ask him to fulfill his wish.The vulture explained all this to Red and even suggested that one of his people - “who does not mind” for the role of a “live master key”. However, Redrick takes Arthur, the son of Barbridge, a handsome man, begged from the Zone, who desperately asked Red to take him with him - Arthur guessed that Redrick was going in search of the Golden Ball. Redrick is sorry for Arthur, but he convinces himself that he has no choice: either this boy, or his Monkey. Arthur and Redrick, having passed through all the traps set by the Zone, finally approach the ball, and Arthur rushes to him, shouting: “Happiness is for everyone! For free! Any amount of happiness! Everyone get together here! Enough for everyone! No one will leave resentful! ” And at that very moment the monstrous "meat grinder", picking it up, twists it, as the housewives twist the linen.

Red sits, looking at the Golden Ball, and thinks: to ask about his daughter, and what else? And with horror he understands that he has no words or thoughts - he lost everything in his stalker sorties, clashes with guards, the pursuit of money - he needs to feed his family, but he can only go to the Zone and sell strange things to all kinds of dark people, who do not know how to dispose of them. And Red understands that he can’t come up with other words, except those that this boy shouted before his death, so unlike his Vulture father, “Happiness is for everyone, in vain, and let no one go offended!”