The Duchess asks York to finish telling her about their two cousins' (Richard and Bolingbroke) arrival in London.
He had left off telling her about the people throwing dust and garbage on Richard's head from their windows. Bolingbroke, York continues, rode on horseback and was welcomed by the people.
The Duchess asks where Richard was riding. York compares Richard's appearance after York to an actor who shows up onstage after the star has left. No one welcomed him. They threw dust at him, which he shook off patiently.
Despite all of this, York says, heaven had a hand in it all, and he and she are sworn subjects of Bolingbroke's now.
Aumerle comes in, and York laments his friendship with Richard, since he's now been stripped of his title. He tells his wife their son isn't Aumerle anymore. He's the Earl of Rutland.
The Duchess welcomes her son and asks him "who are the violets now?" – meaning, who is in favor at the new court? Aumerle says he doesn't know or care. York warns him to be careful or he'll be "cropped" before his time.
York notices a seal around his son's neck and asks to read it. Aumerle tries to stop him but York insists and finds evidence of a conspiracy against Bolingbroke.
Furious, York tells a Servingman to saddle his horse. He swears to denounce his son. The Duchess, perplexed, asks what's going on. Aumerle tells her their son will have to pay for his treachery with his life. York calls for his boots. The serving man arrives with the boots. The Duchess tells Aumerle to hit the serving man. He doesn't, and she tells the serving man to go away.
The Duchess asks York whether he won't hide his son's mistakes, pointing out they're unlikely to have any more sons. York calls her a madwoman and asks whether she really wants to hide "this dark conspiracy" to kill the king at Oxford.
The Duchess suggests they keep their son at home and prevent his participation. York refuses and says he would denounce him if he were twenty times his own son.
The Duchess replies that he would have more pity if he had delivered him himself, and accuses York of suspecting that Aumerle isn't his own son. (She implies that he's accusing her of being unfaithful.) She swears she's been loyal and points out that Aumerle takes after his dad's family more than hers.
York tells her to get out of his way and goes. The Duchess tells Aumerle to try to get to the king before his father does and beg his pardon. She plans to go too.