Part one

In one of the cities of Italy, the old peace-loving Duc, who is the patron of sciences and arts, rules. Duk is so kind that the people are not at all afraid of him, and therefore justice in the Italian city is napping. For a long time, Dook ponders how to fix this problem, and finally decides to put Angelo, an experienced and severe person in his place. Dook himself, without saying goodbye to anyone, sets off to wander.

As soon as Angelo comes to power, the laws begin to work, and executions are held on Fridays. Between the forgotten laws there was one ancient, threatening the adulterous death. Angelo restores him, and the people begin to murmur against the new ruler, and the youth chuckles at him.

The first violator of this law is Claudio - a young patrician who fell in love with Juliet and seduced her. Claudio was going to marry Juliet, but their relationship becomes known, and in court the young man receives a legal sentence.

On the way to prison, the unfortunate Claudio meets Luzio - a rake and a carefree reveler, whom he asks to go to the monastery to Isabela - Claudio's sister - and talk about the grief that happened to him. Claudio hopes that Isabella with her entreaties will soften Angelo’s heart, and thereby help her brother out of trouble.

At this time, Isabela is sitting in a monastery. In a day, she should take the tonsure and discuss it with the nun. At this moment, Lucio appears and reports the misfortune that happened to Claudio. Isabella decides to beg Angelo for mercy for her brother.

Asked by the nun, Isabella, together with Lucio, goes to the nobleman. She begs Angelo for a long time, but he is adamant. Desperate, Isabela declares that Angelo could have committed a similar sin. Angelo darkens and answers: “Leave me, please.” However, Isabela continues to ask what Angelo tells her: Claudio will be executed tomorrow. Then Isabela for the sake of saving her brother offers gifts - her prayers. Angelo dates her the next day

Part two

Angelo realizes that he has fallen in love with Isabela, he thinks about her for the rest of the day. In the morning she comes to him, and a conversation takes place between them. During this conversation, Angelo first hints, and then openly says that if Isabela surrenders to him, he will free Claudio from the death sentence. Isabela accuses Angelo of lying and hypocrisy and leaves.

She comes to the prison, where Claudio is imprisoned and tells him what happened. At first he tells Isabela that there is no need to sin, but then begs his sister to forget about chastity and fulfill the condition of Angelo. Isabela is furious from this offer and is about to leave, but Claudio apologizes and restrains her. Isabela forgives Claudio.

Part three

The conversation between Claudio and Isabela outside the door listened to Dook in the guise of a monk who, as it turned out, did not travel, but to find out the situation in the city, walked in different guises, hid in the crowd, imitating Garuna Al-Rashid.

When the conversation between brother and sister ends, Dook opens the door and quietly calls back Isabela. He reassures her and reports that he has an idea how to expose Angelo: it is necessary that instead of Isabela, his wife Angelo Mariana spend the night with him. Angelo abandoned Mariana due to the fact that there were bad rumors among the people - these were unproven accusations, but Angelo even had this: “Suspicion of Caesar’s wife should not touch”.

Mariana spends the night with Angelo, and he does not notice the substitution. However, he does not fulfill his promise and issues an order for the execution of Claudio; he also orders that his head be presented to his chambers. Then Dook presents his ring and seal to the head of the prison, and thereby stops the execution, and instead of the head of Claudio sends the head of the sea robber who died that night.

Meanwhile, there is a rumor among the people that Dook will return soon, Angelo is embarrassed. Good Dook greets the people and Angelo with a smile, not giving the appearance that he knows everything. Suddenly, a cry is heard, and Isabela falls at the feet of the ruler. Angelo is scared and is trying to make Isabella insane, then Dook reports that she knows about the atrocities of Angelo. Dook orders Isabela and Angelo to go with him to the palace.

In the palace of Maryana (she still loves Angelo with all her heart) and Isabel pray to Dook to have mercy on the criminal, and he, listening to their prayers, forgives Angelo.