|The end has come, my friends. Prepare for the deaths of everyone.|
Act 4 Scene 7
Between this scene and the last, Claudius and Laertes had their little off-screen "trial" to determine if Claudius was guilty of killing Polonius or not. Apparently, it came out favorably for Claudius because he and Laertes are totally bros now. Laertes has come to the (correct) conclusion that Hamlet killed Polonius and asks why Claudius hasn't done something about him yet. Claudius says that it's because of Gertrude, who is, you know, Hamlet's mother for Christ's sake. Also, people generally like him and would be upset if he died. Laertes begins to plot his revenge on Hamlet, which Claudius fully encourages.
Claudius is given Hamlet's letters. You know, the ones he somehow sent from a ship while being held captive by pirates. Totally a normal thing. Anyway, Claudius is confused by his letter, which says that Hamlet will be back in Denmark the following day. Claudius thinks that it must be a trick. Laertes, however, is excited because he knows he will soon have his revenge on Hamlet.