HAMLET                     Give him heedful note,

For I mine eyes will rivet to his face

And after we will both our judgements join

In censure of his seeming.

HORATIO                   Well, my lord

If ’a steal aught the whilst this play is playing

And scape detected I will pay the theft.

Enter Trumpets and Kettledrums, CLAUDIUS, GERTRUDE, POLONIUS, OPHELIA [ROSENCRANTZ and GUILDENSTERN].

HAMLET         [to Horatio]    They are coming to the play. I must be idle. Get you a place.        (3.2.80-87)

Give him heedful note, Hamlet instructs Horatio, him being Claudius, take note of everything he does, every twitch or fidget or grimace, every colour-change or blink. For I mine eyes will rivet to his face. I’m not going to take my eyes off him, not for a moment, and after we will both our judgements join in censure of his seeming. We’ll compare notes afterwards and see if we’ve reached the same conclusions based on how he’s reacted, every last detail. Horatio’s reassuring and also, perhaps, trying to get Hamlet to relax (ha! Hamlet, relax?) just a little: don’t you worry, well, my lord if ’a steal aught the whilst this play is playing and scape detected I will pay the theft. If Claudius so much as picks someone’s pocket—steals their programme, purloins their cushion—and gets away with it during this performance, then I’ll pay the price, I’ll take the punishment and pay compensation too. He won’t get away with anything on my watch. I’ve got this. (Of course Claudius is guilty of theft—of the crown, of Gertrude—as well as murder.)

This has turned into a big court event, it seems, there’s the suggestion of a procession, trumpets and kettledrums, a reminder that—even for this after dinner entertainment—it’s being played before the King and Queen (perhaps it would have mimicked the ceremonies of court performances by the Lord Chamberlain’s Men?) Everyone’s there, including poor Ophelia. And so Hamlet has to act like it’s just another show, not a cunning plan, not like he’s had anything at all to do with it other than asking for a play to be performed. They are coming to the play. I must be idle, unconcerned, and also, I must do that maaaaad thing again. (He’s already gone into prose, which tends to characterise his antic disposition.) Get you a place. Go on, hurry, find a seat—and he might nod at one which will give a good view of Claudius, perhaps one that will balance his own. Sit there, please, Horatio?