Answering your own question, are you, Ophelia?
Ask a madman a question, get a mad answer, I guess. But – this is where I’m not entirely sure why Ophelia asks for meaning of the show – since she’s clear on what it was. She’s got it worked out pretty well, so her question might reference some other. “This” entirely – an action perhaps, a gesture.
She’s like, “No, Hamlet – it’s not mischief. It’s a plot summary. It’s a dumb show. We all know it’s not miching mallecho.”
Except of course it is mischief – but no one knows that but Hamlet and Horatio.
Even Claudius doesn’t seem to figure out the mischief bit. He just gets hit with it – straight into his conscience, straight into his guilt ridden guts.