The confidence of the humanity – or, at least, of the State authorities – in the assuming of an absolute happiness is so great as its supposed to transfer this happiness even to other planets. For this purpose, under the managing of D-503 (names of course are replaced by figures and letters) is constructed the „Integral" – a rocket-plane for interplanetarian communications. Around the builder of this rocket-plane M-2 D-503 is developped the main intrigue.
D-503 is evidently one of the most able engineers of his epoch and he seems to be one of the most typical representatives of the mechanized „happy" humanity. During the usual walk (accompanied by the music of „Musical Works" trumpets) D-503 makes the acquaintance of a woman 1-330 which posseses some irony, has something incomprehensible for D-503 and therefore hostile for him as for the rationalized man; nevertheless this „incomprehensible" is attracting him, to his astonishment.
1-330 presents to him a „rosy ticket" and D-503 comes to see her at the appointed time. As it is used here in such a case, at the glass room are already lowered the curtains, but instead of simple „rational act" the hostess 1-330 smokes, to awe of her visitor, ancient „cigarettes"; she drinks some green spirit drink and the worse, while kissing makes him to gulp it too. These poisons – nicotin and alcool at the rationalized State, had been, of course, prohibited by a long ago and D-503 ought to go to the State’s „Guardians’ Bureau" and to let them know the crime, but he does not feel he has enough force to do it and because of this he himself becomes a part of the crime…
By-and-by he is convinced that he got this dangerous illness – „love about which he has read but in ancient books of the 20-th century… This is complicated with his relations to some other woman 0-90; it appears that even such a „nonsense" as a jealousy is existing, not only in the ancient books, for 0-90 is jealous of him regarding 1-330. And what is still worse – 0-90 likes to bear a child of him, though she has not right to do it, for she does not satisfy to the „Mothers’ Standard" set off by the State. In the paroxysme of desasperation and weekness of will, D-503 agrees to give her this child and the woman 0-90 is threatened in the nearest future with the awful „Gooddoers’ Machine" (the „Gooddoer" is a State’s Chief, elected every year, and he is executing by his own hands the annihilation of criminals by means of this Machine; it is a very quick and esthetic operation – the dissociation of matter with some rays and after a second of what once had been a man was not left but a plash of water and a handful of ash…).
In the meantime meetings of D-503 with this misterious woman 1-330 are going on. One of meetings is arranged at „The Ancient House", which has been kept, as a musem example, from times of 20-th century. Here 1-330 receives D-503, having put on a fascinating „ancient" dress of 20-th century, instead of the usual grey-bluish uniform. While changing this dress again for the uniform, she asks D-503 not to look at her for a time. He does not see her but hears the rustle of the silk, the screak of the mirror door of a wardrob, he wants to rush to her, to embrace her… But when he turns, he sees that 1-330 suddenly vanished – where to and how it is quite inconceivable…
During some days he is looking for her, longing at her. There happen some dramatic encounters of D-503 with the woman 0-90 who is in await of a child and then – of death under the terrible „Machine". D-503 finds the only forgetting in his work. The „Integral’s" construction is already ended and soon has to proceed her „maidenflight" in the stratosphere.
Grieving, D-503 comes once more to this room of the „Ancient House", where took place his last rendez-vous with 1-330. He opens the wardrob door – and behold! – the floor of the wardrob is coming down under his feet, he is lowering somewhere down further and further and at last sees himself in some subterraneous place. He considers that this probably is a place where has been the „undergrounds" of the „ancients" of 20-th century. But why then this place is now lighted with electric bulbs? Looking for an exit of this labyrinthus he comes to some door, behind which some voices are heard. He knocks at the door and his acquaintance, a doctor, to which he applied recently to be cured of „love", comes out to meet him. The doctor, without any explanations, is hastily leading him out to the yard of the „Ancient House"…