The investigators track a double-crossing "Bonnie and Clyde" couple whose nine bloody victims include two undercover police investigating an illegal gun-running ring. To gain a foothold on slim evidence, Loginov focuses on the mental processes of one suspect - and he knows that his female companion pulls the strings.

The famous cardiac surgeon Leonid Feldman was shot dead in a restaurant toilet. Suspicion falls on the ex-wife of the murdered Veronica, who accused him of harassing their young daughter Sonya, and then on Veronica's sister Serafima Linkova. However, Sonya denies the accusations against her father. Upon learning of this, Seraphima leads the investigation to the real killer ...

A student of the architectural institute was killed on the square of the Leningradsky railway station. The attention of investigators is attracted by a famous architect, whose work was fond of the murdered. It turns out that the architect is married to three women at once, one of whom is pregnant, and the student is the architect's illegitimate son ...