act 4 scene 7

 Claudius and Laertes plot to find a means of killing Hamlet without upsetting Gertrude or the people. They propose to arrange a duel between Hamlet and Laertes, both of whom are accomplished swordsmen, though Laertes is the more reputed. Claudius suggests that Laertes be given a sharp sword while Hamlet’s remains blunt. Laertes does him one better, saying that he will dip his sword in poison so that the least scratch will kill Hamlet. Claudius says that on top of this he will prepare a poisoned cup and give it to Hamlet during the fight.