] What do you make of Polonius' previous acting experience? "I did enact Julius Caesar: I was killed i' the Capitol; Brutus killed me."

Maybe he remembered falling at the hands of the assassins with special dramatic style. The scene may have stood out in his mind because of the gory spectacle involved. Something else that strikes me is the way he uses the first person -. Doesn't he differentiate between the actor or the character, between real murder and stylized, pretend murder?

Aside from the question of why he would overexplain, it is a creepy allusion given that a similar assassination to that of the play had just occurred in Denmark, and that Polonius will be actually murdered in a manner as foolish as any of his speeches.