Hall in the Holy Rood Palace. He says the city has riots. Someone unfamiliar to him at the head of the crowd - mummers, masked, dancers with bells, people in black hoods - threatened, predicted and urged the people not to obey the queen. The courtier of Queen Riccio confirms that he also watches from time to time as people eagerly listen to these sermons. The page further tells that the people burst into the queen's chapel shouting: “The nest of the papists!”, That the buffoon of Darnley, the queen’s husband, jumped up to the altar and began to pretend to be a sermon, and the people answered him with mocking couplets. Queen Mary Stuart in despair. She feels the hatred of the people; most of the courtiers have left her; she wonders how her Christianity can be so different from the Christianity of the people of Scotland. Riccio proposes to immediately prepare a decree punishing those responsible for the riots. Maria dictates his page, the page clarifies whether to enter the name of Heinrich Darnley, the husband of the queen. Mary hesitates; she suspects that the riots were inspired by him - after all, the crowd was led by the king's buffoon. Here Riccio reminds her that she is the queen; she is like the sun, and she has the right to punish from God. He demands to immediately call the duty officer to announce the Queen’s decree. Douglas enters. Maria tells him to take the paper to Royal Chancellor Morton, so that he would stamp. Douglas scans the decree and sees that it does not have the name of the king. He asks the queen about this. Riccio is responsible for her. Douglas is losing his temper. He urges the queen not to use bloody suppression measures, hints that he sees this as French or Italian influence. But the queen coldly reminds him of her power to eliminate the subjects disobedient to her will. A quarrel erupts between Riccio and Douglas, Douglas challenges Riccio to a duel and swears that he will kill the Venetian tomorrow. The queen leaves and takes Riccio away. Douglas is left alone, he is considering a duel. Morton enters. Douglas shows him the decree. Morton is indecisive: he is afraid of the wrath of both the king and the queen. Without stamping, Morton bids the king. At this time, Henry was engaged in a conversation with his jester Nick, who teases him with the fact that the queen has real power in Scotland, and Henry is only her husband, that the queen chooses close ones, for example, this Italian harpist Riccio ... At this time, Morton brings an unfortunate decree. King in anger, he decides to kill Riccio. King Lindsay enters the court, he calls the king to hunt with the newly acquired falcon. Morton replies that the king already has an occupation today. Lindsay willingly joins the plot against Riccio. He literally forbids killing Riccio tonight, because he must kill him tomorrow morning. Then Henry, taking advantage of the delay, sends the jester to the astrologer to find out what the location of the stars is for his intentions.
The astrologer in his laboratory (he is also an alchemist) argues with himself that experience confirms the futility of science, that purpose, the will of the stars dominate man, dispose of good and evil. Nick comes in, sprinkles with witticisms, the astrologer is not inferior to him in wit. Nick reports that the king sent him to ask about Riccio’s fate and tells the astrologer to predict Riccio’s death. The astrologer replies that the stars will tell him, not people, and in turn predicts the death of the jester. With that he leaves. The page of the queen caused by the astrologer appears. Page loves his mistress. The astrologer tells him to tell the queen that today the man she loves will die. “How, Botwell will die today?” - exclaims a page. The astrologer is puzzled. He had in mind Riccio and is rushing the page to warn him about this. Left alone, the astrologer wonders - it also appeared from the stars that Botwell was somehow darkly connected with the queen - through Mars, Saturn ... Botwell enters. From his monologue, it becomes clear that he unexpectedly found himself in the house of an astrologer. Realizing where he got, Botwell asks the astrologer how much he has left to live. The old man replies that three years and that Botwell will be king. The botwell takes out a bottle of poison with which he wanted to commit suicide, wants to throw it away - and hesitating. Indeed, in the atmosphere of palace intrigues, any weapon will come in handy. He's leaving.
The page tells the queen that Riccio will come soon. The Queen is looking forward to him - in her opinion, he alone remained faithful to her. “And Botvel?” The page asks. “Who is Botvel?” - the queen is interested. A surprised page tells Mary how, while boating, a strong wind plucked a rose from the head of the queen, a flower fell into the water. And then one of the courtiers - Botvel - rushed into the boat and scaredly chased the rower to catch a rose from the water. After hearing the story, Mary sends a page to pray. She confesses to God that she has no more strength to resist her love for Botwell. The Queen knows that at court she is considered in love with Riccio. Riccio enters. Mary reports a mortal danger that threatens him and coldly says goodbye to him, pointing him to the ship that will take him to Rome. In desperation, Riccio tries to beg the queen to cancel the decision to leave. The queen is adamant.
Heinrich, Morton, and Lindsay learned about Riccio’s impending departure and hastily conferred to kill him or let him sail. Then Douglas appears and reports that Riccio has already sailed. Douglas in despair, he longs for bloody revenge, his knightly honor is hurt. Suddenly they meet a page that brings the queen a note from Riccio - he did not leave and will be with her in the evening. The conspirators take away the note.
Maria is busy embroidering in her room. Riccio, who came, explains to her that he could not leave, because he has a duel with Douglas in the morning. He admits that he does not need life without her love. He asks Maria to give him a wreath of roses - he will plant flowers on the altar in Rome ... Henry, Douglas and Dindsay come in and kill Riccio. Queen faints. Douglas is struck by shame and horror - he voluntarily retires into exile. Henry is worried if the queen will hate him. Lindsay takes the king away, whispering to him about the upcoming hunt. Queen Botwell is invited by Queen. Mary comes to her senses, sees Botvel and confesses his love to him. The botvel forces her to admit that she wants Henry's death and gives her her bottle of poison, saying that this is a sleeping pill. Mary gives the king this "medicine", but the poison drinks the buffoon. However, nothing can stop the murderous intrigue - Botwell blows up the house of King Henry. In the distance, the growing cries of the crowd are heard. The botvel with the queen are hiding.
