In the King's palace in London, the King and the Prince talk. The King says he thinks God must be punishing him through the misdeeds of his son. How else can he account for the fact that Hal wastes his time keeping such low company? The Prince admits he is guilty of some offenses. But he also says that many of the charges are false, and when he has refuted those, he hopes he may be forgiven for faults that he in his youth has been guilty of.
The King says God may pardon him. But he has more questions for Hal. He wonders why Hal has allowed himself to be alienated from the court. His younger brother, John, has usurped his place in the king's councils. Great things were expected of Hal, but now everyone awaits his downfall.
The King then talks about his own life and political strategy. Before he overthrew Richard, he made a point of being only seldom seen in public. Then when he did show himself, he made much more of an impact, and won more followers, than he otherwise would have done. He contrasts his own strategy with the practice of Richard II, who made himself too familiar with the common people, and as a result fell in public esteem. People had seen too much of him.
King Henry then compares Richard II to Prince Hal. As with the former king, people are weary of seeing too much of him.
Prince Henry promises to reform, but the King has not finished with him yet. He contrasts Henry unfavorably with Hotspur, whose deeds he describes in heroic terms. Then he talks about the armies arrayed against him, but stops himself, wondering why he bothers to tell Harry, since he fears that Harry will as likely as not join with Hotspur and fight against his own father.
The Prince emphatically denies this. He says he will redeem himself, and prove himself his father's son. He promises to meet Hotspur on the field of battle and defeat him. The King is impressed with his son's resolve and sincerity, and says that from now on he will trust him.
Sir Walter Blunt enters and announces that the rebels have raised a mighty army at Shrewsbury. The King already knows this, and says that Westmoreland and John of Lancaster are already on the march. He tells Prince Hal to set off the following Wednesday. He, the King, will follow the next day. He is confident, realizes the urgency of the situation and acts decisively.
The hints dropped earlier, that a change would soon come in the Prince, come to fruition in this scene. In his audience with the King, Prince Hal speaks in a language that we have heard only once from him before. With his pals, he speaks in prose, as they do, but with the King, he speaks a stately blank verse, as befits his new resolve. In this scene he reveals a depth of character, a sense of duty, that has not been seen before. Once again, Hotspur is presented as a point of comparison. The King speaks highly of Hotspur and contrasts him with the behavior of his own son. And when the Prince makes his speech promising to redeem himself, he frames it in terms of a personal combat with Hotspur.
The fact that the King speaks at length, explaining his actions from the past, suggests that he has a strong need to justify the fact that he seized the crown from the legitimate king. This is the one scene in the play in which the King appears in a private rather than public setting. It is clear that he carries a heavy burden, and he wonders whether God is punishing him, through his son's behavior, for his sins. It is as if he has a need to confide in someone, and he chooses to do so with his son, even though the two men are hardly close, and do not in this scene show much warmth for each other. What is discussed is duty, not love between father and son.