A famous St. Petersburg antique dealer dies at the hands of the raiders. Criminal investigation trainee Denis Belov goes on his first assignment - to interview a witness to this crime. The witness turns out to be a girl of amazing beauty who behaves very suspiciously, so her involvement in the murder is obvious. But not the future great investigator Belov, who... falls madly in love with her! However, the criminal investigation does not tolerate sentimentality: a trainee overwhelmed by feelings makes a number of mistakes, and it takes Denis and his managers a huge amount of time and effort to correct them. And the murders of antique owners continue...