Prince Hal and his pal Sir John Falstaff indulge in some good-natured banter at the Prince's lodging in London. The Prince ribs Falstaff about being lazy, drinking too much and hanging out at brothels. Falstaff takes it all in good humor. He acknowledges he is a thief, and says he hopes that when Hal is king, Falstaff and his friends will still be allowed to continue their thievery. Hal replies by pointing out in a roundabout way that thieves go to the gallows. Falstaff quickly changes the subject, and tries to engage Hal in a conversation about the hostess of the tavern they frequent. But Hal's earlier remark is still on his mind, because he then asks whether there will still be gallows standing in England when Hal is king. He asks Hal not to hang a thief. When the Prince replies, "No; thou shalt," Falstaff takes this to mean that he will be appointed a judge. But Hal says he meant only that Falstaff could become a hangman. Falstaff seems to like this, since the hangman receives the clothes of the executed man.
The two men continue to banter, and it is clear that Falstaff is very fond of this "rascalliest, sweet young prince." He pretends that Hal has corrupted him, when in truth it is probably the other way round. Hal's next remark, inquiring about where they are to commit their next robbery, seems to confirm this.
Poins enters, and Falstaff says that now they will know whether Gadshill, one of their little gang, has set up their next robbery. Poins confirms that a robbery has been planned for early the following morning. It is to take place at Gad's Hill, on the road from Rochester to London. Poins says there will be pilgrims going to Canterbury taking expensive offerings for the shrine at Canterbury Cathedral, and also rich traders on their way to London.
When he hears this, Falstaff tries to persuade Hal to be a part of the robbery, but the Prince refuses. Poins says he will be able to change the Prince's mind if he can have a word with him in private. Falstaff leaves. The Prince agrees to take part in the escapade after Poins explains that he plans to play a trick on Falstaff and the other robbers, Bardolph, Peto and Gadshill. Poins's plan is that he and Prince Hal should not take part in the robbery. But then, after the robbery has been done, they will waylay the robbers and rob them. Poins knows that later on Falstaff will wildly exaggerate about how many men robbed him, and how stoutly he defended himself. Poins and the Prince will then be able to disprove what he says. Poins thinks this will make an excellent joke.
After Poins exits, the Prince, in a soliloquy, reveals that he is only going along with his friends from the tavern for a while. Soon he will reform his behavior and prove that the low expectations everyone has of him are wrong. The sudden change in him will attract more notice, and win him more respect in the eyes of others, than if he had never developed a bad reputation in the first place.
Having heard from the King about Prince Hal in the previous scene, we now see him in person behaving much as we have been led to expect. This scene is a comic contrast to the first scene, with the planned robbery at Gad's Hill a kind of parody of the more serious battles going on elsewhere in the kingdom. (This is also apparent in the style. The nobles speak in blank verse, but the low characters, including the Prince, speak prose.)
However, Shakespeare is careful not to present the Prince in too bad a light, which would make it more difficult for the audience to respond positively to him when he makes his reformation. Although he knows about the robbery at Gad's Hill, he does not take part in it. His part is limited to robbing the robbers-it's just a lark. And the Prince's soliloquy at the end of the scene reveals that he is simply biding his time. He plans to throw off his low companions at a time of his own choosing, and he believes that after he has done so he will be more revered than he would have been had he not consorted with them in the first place. Ironically, critics have often taken issue with Prince Hal over this speech, arguing that he sounds calculating and duplicitous.
There is also a contrast in this scene between Falstaff's promise to reform ("I must give over this life, and I will give it over!"), which he makes several times in the course of the play and never keeps, with Hal's similar revelation at the end of the scene, a promise which he does keep.