At the castle in London, King Henry tells his people to scram so he call yell at his son in private.
According to the king, Prince Hal was sent to earth by God to punish him for his past sins. (Hmm…Henry must be thinking of the time he stole the crown from King Richard II and then had one of his goons murder him.) Why else, asks King Henry, would a prince act like such a total loser?
Hal asks for forgiveness and hints that he'll "purge" himself of his bad behavior. (He doesn't tell the king about his master plan to dazzle everyone by staging his own reformation.)
The king launches into a long list of why Hal's such a degenerate: Hal's been kicked out of the council and replaced by his little brother, he's alienated himself from the nobles at court, he's let down just about everyone who ever had high expectations of him, and everybody thinks he's on a major downward spiral.
The king gives Hal some advice about how to manage his public image and tells him to quit hanging out with the commoners because it's bad public relations.
Unlike King Richard II, the "skipping king," who was a total clown and didn't know how to keep his public image fresh, King Henry knows how to keep his subjects loyal.
Prince Hal promises to be good.
But, Henry's not done. He compares Hal to Hotspur and says (in so many words), "Why can't you be more like that guy? He's the same age as you but he leads older men into battle and mops the floor with his enemies on a regular basis while you're clowning around in taverns."
Hal stammers at first but then delivers his own lengthy speech. Those who have been bad mouthing him to his dad better watch out because the prince is going to redeem himself by killing Hotspur at the upcoming battle at Shrewsbury.
King Henry says "fine" and puts Hal in charge of a bunch of troops.
Sir Walter Blunt enters with news that Douglas and the English rebels have met at Shrewsbury and have amassed a big, scary army.
Henry says he's gathering forces too in preparation of battle. He gives directions for Westmoreland, Prince John, and Prince Hal to meet up in about twelve days.