In this very long scene, Polonius is telling the king and queen that he has found out why Hamlet has supposedly gone mad. He explains that because he took Ophelia away from Hamlet, he has been driven mad by love. Hamlet is then with Rosencrantz and Guildenstern (his two best friends) and tells them that he isn’t mad he is just putting on an act. Actors arrive to try and entertain Hamlet. Throughout the entire scene Hamlet is taking the mick out of Polonius. He is constantly making snide comments about his appearance etc. Finally, when Hamlet is alone he tells himself that he needs to create a play so that it mimickes his fathers murder. This is in order to see if his uncle/dad/king reacts when he sees this play. This is so Hamlet has concrete evidence against the king so he can kill him with confidence knowing that he is doing the right thing (and also obeying the ghosts’ command).