A Siberian city. A private house of the Korostylevs family on the outskirts of the city. A week after the death of Anatoly Ivanovich - he died in a hit-and-run accident - his son Sergey (Aleksey Morozov), daughter-in-law Olga (Anna Miklosh) and grandson Andrew experiencee a new shock. Valentina Vasilievna (Irina Rozanova) appears in their life - she is Anatoly Ivanovichs ex-wife and Sergey's mother, whom everyone considered dead for a long time. The mother tells Sergey that his father had left her hopelessly ill with tuberculosis almost thirty years ago. However, she survived, met a lot of misfortune over the years and now decided to find her son. Sergey is so happy to see his mother again, that he doesnt notice how she gradually and deliberately starts destroying his family, breeding mistrust towards his wife. Behind the mask of an unhappy abandoned woman we gradually see a heartless and cruel creature.