After the tragic death of his wife, the provincial surgeon Sergei Vinogradov does not have a closer person than Dasha, the ten-year-old daughter of the deceased. And the girl herself treats him like her own father. Secretly from his relatives, Sergei leaves the hospital, sells the apartment and, against the will of Dasha's grandfather, takes her to Moscow. Full of hope for a happy life, the heroes accidentally end up on the notorious Cherkizovsky market, where the girl disappears without a trace.