The Tsar's Bride
Griaznoy is an oprichnik.  Although he already has a lover, Lubasha, he now decides he loves Marfa, the daughter of the merchant Sobakin.  Marfa is already engaged to be married to Lykov, a boyar.  There is much merrymaking and singing at a feast.  Then Griaznoy asks to be left alone with Bomelius, the tsar’s doctor.  He asks him to get him a love potion. Lubasha, who is hiding, hears what he says and realizes that he does not love her any more.  When the doctor goes, Griaznoy is horrible to Lubasha and tells her to go.  She now wants to talk to Bomelius.