Of course, it's unpleasant to find out that a colleague came up with an offensive nickname for you "Hippo with mayonnaise", but Tatyana Sergeeva has no time to get upset because of nonsense. Professor Aleksey Burkin turned to the office of the special brigade: it seems that one of the family members is pouring a strong laxative on the doctor. At first glance, the situation is utterly stupid, most likely it is someone's prank. According to the professor, everyone in their family is kind to each other, and yet he needs to bring the attacker to clean water. The detectives decide to send Tanya to Burkin's house under the guise of his relative from the Far East, Louise. Allegedly, she came to Moscow on business. It turns out that not good relations reign in the professor's house. Daughter-in-law Irina rushes at everyone in anger, and the second daughter-in-law, confectioner Lyuba, on the contrary, is sickly to the point of nausea. And Sergeeva begins an investigation. Timofei Volynov, a search specialist, comes to Burkin. After drinking the compote brewed for Alexei, he loses consciousness. Who could have poisoned him and why? The detectives of the special brigade find out that in the childhood of Alexei's wife there was a black spot. This discovery allows them to reach out to the intruder. But ... all of a sudden it turns out to be completely different! In appearance, the harmonious and logical pyramid of evidence instantly collapsed and turned into ruins.Daria Dontsova is the most popular and sought-after author in our country, the favorite of millions of readers. More than 200 million copies of her books have been sold in Russia.Her work fills hearts and souls with light, optimism, joy, and confidence in the future!