Sergei Pronko's corpse was found in the apartment. The apartment belongs to his grandmother, who recently died of a heart attack. Suspicion falls on Borisov, who took care of the old woman while the grandson was losing her money in the casino. A will for the apartment was also drawn up for Borisov. From their neighbor's stories, it turns out that before her death, the woman began to hear the voice of her deceased husband. Mukhtar finds a hidden tape recorder in the piano with a recording of a mysterious voice...

A sobbing Anya resorts to the police, whose insidious girlfriend Luda cunningly took her newborn son and disappeared with him. Artyom, Vadik and Lena are trying with triple energy to help the unfortunate woman find her baby. Fortunately, Mukhtar discovers a recipe from the dairy kitchen in the corner of the room that Luda rented — this turned out to be enough to restore the full picture of the crime...