Ok, so there is some pretty dramatic stuff going on in the singular scene of act 4. This is where the proverbial shit hits the fan. What was most dramatic, aside from Aumerle basically saying "I'ma take on all you Mother Fuckers who call me a liar," (Pardon the French) is the dramatic role shift of Harry and Richard.

When the play started out, everyone seemed to be cheering for anyone who was willing to take out the "evil" King. Harry took on that challenge so we, as an audience naturally trusted him to do the right thing. But now that Richard has essentially been defeated, Harry shows his true colors. He seems to have some dark intentions of his own, though they may not involve the murders or banishments of his kin. He may not want to get his hands dirty and will just let them duke it out and kill each other. After all, that's what he was practically doing in the beginning of the scene. There is also the possibility that he is an earnest person, but he is still so vexed by his fathers murder that he won't rest until he knows for sure what happened to him, but that seems rather unlikely. As for Richard, without the weight of his crown and with the knowledge that his plot failed horribly, he has a new sense of humility. He seems to see right through Harry when he tries to make him read his crimes outloud. All Harry is trying to do is get the people to side with him, otherwise he could have just killed Richard and been on his merry way. It's all about apearances.

*Tina