Teni staroi kvartiry [Shadows of an Old Apartment]

1959 year. In the city of Leningrad, in a communal apartment, an old woman was poisoned by one of the inhabitants of the apartment - God's dandelion from the 'former'. Then the perpetrator was never found. And now, half a century later, Maria Karavay takes on the investigation of an old murder. The world-famous cellist Ksenia Averintseva buys an apartment overlooking the Griboyedov Canal. Upon learning of this, her grandmother dies of a heart attack. By a fatal coincidence, she lived in that old apartment and was a suspect in a never-solved case. But Xenia cannot believe that her grandmother is a murderer.