The action takes place in the USSR in the summer of 1928. Vladimir Ipatievich Persikov, professor of zoology at IV State University and director of the Moscow Zoo Institute, makes a scientific discovery of great importance: he sees an extraordinary ray in the eyepiece of a microscope when the mirror and lens accidentally move — the “ray of life” as the assistant professor later privat docent Pyotr Stepanovich Ivanov calls him. Under the influence of this ray, ordinary amoeba behave in the strangest way: there is a frenzied, overturning all natural-science laws reproduction; newly born amoeba violently attack each other, tear to shreds and swallow; the best and the strongest win, and these best are terrible: they are twice the size of ordinary specimens and, in addition, are distinguished by some special anger and playfulness.

With the help of a system of lenses and mirrors, privat-docent Ivanov constructs several cameras in which, in an enlarged view, outside the microscope, he receives the same, but more powerful beam, and scientists are experimenting with frog caviar. Within two days, thousands of tadpoles hatch from eggs, growing in such evil and gluttonous frogs per day that one half immediately devours the other, and the survivors in two days without any ray produce new, completely countless offspring. Rumors about the experiments of Professor Persikov seep into the press.

At the same time, a strange chicken disease, unknown to science, begins in the country: having become infected with this disease, a chicken dies within a few hours. Professor Persikov is a member of the emergency commission against chicken plague. Nevertheless, after two weeks in the territory of the Soviet Union, all chickens die out to one.

In the office of Professor Persikov, Aleksandr Semenovich Rokk, just appointed the head of the indicative state farm “Red Ray”, appears, with “paper from the Kremlin”, in which the professor is invited to submit the cameras he designed to Rokka “to increase the culmination in the country.” The professor warns Rocky, saying that the properties of the beam are not well understood, but Rocky is absolutely sure that everything will be in order and he will quickly breed beautiful chickens. The people of Rocca take away three large cameras, leaving the professor with his first, small camera.

Professor Persikov for his experiments writes out eggs of tropical animals from abroad - anacondas, pythons, ostriches, crocodiles. At the same time, Rocke also writes chicken eggs from abroad to revive the culinary industry. And a terrible thing happens: orders turn out to be confused, and a parcel with snake, crocodile and ostrich eggs comes to the Smolensk state farm. Unsuspecting Rokk puts unusually large and some kind of strange-looking eggs in the cells, and right there in the vicinity of the farm all the frogs fall silent, take off and all the birds fly away, including sparrows, and in the neighboring village dogs begin to howl sadly . After a few days, crocodiles and snakes begin to hatch from the eggs. One of the snakes, which grew to an incredible size in the evening, attacks the wife of Rocca Manya, who becomes the first victim of this monstrous misunderstanding. Rokk, who immediately turned gray, before whose eyes this misfortune happened, came to the administration of the GPU, talks about the monstrous incident at the state farm, but the GPU employees consider his story the fruit of a hallucination. However, having arrived at the state farm, they are horrified to see a huge number of giant snakes, as well as crocodiles and ostriches. Both authorized by the GPU die.

Terrible events are taking place in the country: artillery shells the Mozhaisk forest, smashing crocodile egg deposits, in the vicinity of Mozhaisk there are battles with ostrich flocks, huge hordes of reptiles from the west, southwest and south approach Moscow. Human sacrifices are innumerable. The evacuation of the population from Moscow begins, the city is full of refugees from the Smolensk province, martial law is being introduced in the capital. Poor Professor Persikov dies at the hands of an angry mob, who considers him the culprit of all the misfortunes that have befallen the country.

On the night of August 19 to 20, an unexpected and unheard of frost, reaching −18 degrees, lasts two days and saves the capital from a terrible invasion. Forests, fields, swamps are littered with colorful eggs, covered with a strange pattern, but already completely harmless: frost killed the embryos. Countless corpses of crocodiles, snakes, and ostriches of incredible size rot on the boundless expanses of the earth. However, by the spring of 1929, the army was putting everything in order, clearing forests and fields, and burning corpses.

The whole world has been talking and writing about the extraordinary ray and catastrophe for a long time, nevertheless no one is able to get the magic ray again, not excluding the privat-docent Ivanov.