Following the audience with the king, the Percies are on the verge of rebellion. The action in the main plot has risen to the point where the conflict is brought into the open. Augmented by the Scottish and Welsh forces, the Percies will then confront the usurper Henry IV. Hotspur is to pacify Henry IV for the time being by turning the prisoners over to the Crown, but he will make peace with Douglas and soon will ally himself with Glendower and Mortimer. Only after Northumberland has succeeded in calming his son can Worcester proceed. Henceforth, he declares, he will dedicate himself solely to opposing 'this Bolingbroke' and the Prince of Wales. Hotspur is exhilarated by the very mention of a dangerous exploit to be carried out in the name of honor. Worcester interrupts to announce that he has a plan, one 'deep and dangerous,' which he will reveal to his kinsmen. When Hotspur says that the king turned pale at the very mention of Mortimer's name, Worcester replies, 'I cannot blame him.' And this leads to a review of past events: Richard II's designation of the Earl of March as his heir to the throne, the role of the Percies in Bolingbroke's successful revolt, and the ignominious position in which this proud and ungrateful Henry IV has placed the members of the House of Percy. Just as Northumberland urges his son to control himself, Worcester returns to hear another outburst from his nephew. Even though he risks his life he will not obey King Henry. Ordering Hotspur to talk no more of the Earl of March, he adds: 'Send us your prisoners, or you'll hear of it.' The king and members of his retinue leave. He is convinced that young Percy intended to use the Scottish prisoners in bargaining with him for the ransom of Mortimer, Earl of March, Hotspur's brother-in-law, whom he denounces as one who foolishly betrayed the forces he led and now has married the daughter of his captor, 'that great magician, damn'd Glendower.' Hotspur vehemently defends Mortimer, but the king refuses to believe that he is not a traitor. Although the loyal Sir Walter Blunt puts in a good word for Hotspur, the king does not accept this excuse. Battle weary, he found it impossible to respond affirmatively to the request made by the king's messenger, a pretentious, unmanly coxcomb. Hotspur, he states, has been maligned, for his son never intended to ignore a royal command.

Now it is Northumberland who addresses Henry IV, voicing words of conciliation. The king promptly orders Worcester to leave.

His threat to use force if necessary to curb their opposition leads Worcester to remind him that they, the Percies, were largely responsible for his rise to the throne. A determined King Henry strongly reproves the Earls of Northumberland and Worcester, and Hotspur, who have obeyed his summons to appear before him.

Henry iv part 1 act 1 scene 1 summary