The main character is Jakób Szela, also called Kóba, a poor peasant who works for a Jewish family and experiences humiliation and violence from his landlord, Wiktoryn Bogusz. He dreams of becoming a rich and powerful man and escaping his difficult life. During his journey, he enters a mysterious forest and meets magical snakes. They offer to grant him one wish, and he wishes to become a lord. His story develops through a combination of realistic events and magical experiences. The novel follows his personal transformation and the growing conflict between peasants and landowners. These events are connected with the Galician peasant uprising of 1846, during which peasants attacked manor houses and killed members of the nobility.

The book presents the unequal social system of nineteenth-century Galicia and shows how power was divided between the wealthy landowners and poor peasants. Serfdom meant that peasants had very limited freedom and were forced to work for their landlords. Their lives were controlled by people who had economic and social power over them. Rak describes violence, exploitation, poverty and the lack of basic rights. He also shows that even when laws existed to protect peasants, they were often ignored by powerful landowners. The book therefore raises questions about social justice, freedom, equality and the abuse of power. Another important political aspect of the novel is its different presentation of Polish history. Traditional historical narratives often focused on the nobility, national heroes and the struggle for independence. Rak gives attention to the history of ordinary peasants, whose experiences were often forgotten or ignored. He challenges the traditional image of Poland as a country mainly built on noble and aristocratic traditions. The novel suggests that Polish history should also be understood through the experiences of poor people who suffered under the system of serfdom.

The historical figure of Jakub Szela is also presented in a complex way. He is not simply shown as a hero fighting for the freedom of the peasants. The novel explores his ambition, anger, desire for power and need for revenge. Rak does not present him as a perfect leader of a social revolution. Instead, he shows how a person who experiences oppression can also become capable of violence and oppression. It also raises questions about whether violence can be justified as a response to injustice. Although the story takes place in the nineteenth century, the problems it describes can still be recognised in modern society. Economic inequality, exploitation of workers and the division between powerful elites and poorer social groups remain important social issues. Rak suggests that historical forms of dependence may disappear, but similar social inequalities can continue in different forms.

The novel has had several Polish editions and reprints, including editions published in 2020 and 2024. It has also been translated into four foreign languages: Czech (Báje o hadím srdci, 2023), Russian (Сказ о змеином сердце или Второе слово о Якубе Шеле, 2022/2023), Ukrainian (Легенда про зміїне серце або Друге слово про Якуба Шелю, 2023), Hungarian (A kígyószív legendája, translated, 2023)