Nina's son Kirill is accused of setting fire to a businessman's car. It turns out that the crime was committed by Kirill's twin, born with a heart defect and abandoned in the hospital. The found son cannot forgive Nina for her betrayal.
Everything changes in the life of lonely music teacher Nina when her son Kirill is accused of setting fire to the car of businessman Igor Samoylov. A lawyer, the father of one of the students, comes to Nina's aid. Boris has long been unrequitedly in love with her. He finds out that the crime was committed by a guy very similar to Kirill. Then Nina realizes that it can only be one person - eighteen years ago she left one of the twins in the maternity hospital, who was born with a heart defect. Nina's husband and mother insisted that she give up her sick baby. Realizing that her son was alive, she vowed to find and beg his forgiveness. However, the found son is not happy about the appearance of a new "mother" in his life: he considers a completely different woman to be his mother and cannot forgive Nina for her betrayal.
