A fairy tale for children of primary and secondary school age. The main characters are children – Irinka (Caramel) and Romka (Rogalik). In the first book, children from our time find themselves in the fairy-tale country of Marmeland. Their goal is to return home, but they can only do this by defeating the evil sorcerer Vinegar and freeing the fairy Gourmand. Helping the residents of the country in the fight against the sorcerer, children have to complete several tasks using knowledge of physics and chemistry. In the second book, the inhabitants of the country of Marmeland turn to Caramel and her friends for help. Children, again using knowledge of physics and chemistry, help fight the consequences of destruction created by the evil sorcerer Vinegar.