HAMLET         O villainy, ho! Let the door be locked.

Treachery! Seek it out. [Exit Osric.]

LAERTES        It is here, Hamlet, thou art slain.

No medicine in the world can do thee good:

In thee there is not half an hour’s life;

The treacherous instrument is in thy hand

Unbated and envenomed. The foul practice

Hath turned itself on me. Lo, here I lie,

Never to rise again. Thy mother’s poisoned –

I can no more – the King, the King’s to blame.        (5.2.296-305)

Hamlet seems to have considerable presence of mind in the moment, but he’s not yet realised just how bad things are; he’s mostly reacting to his mother’s collapse and death, presumably suspecting Claudius? O villainy, ho! Gotcha! Let the door be locked; it’s as if he imagines some larger plot, and any further enemies outside need to be repelled, any enemies inside need to be prevented from escape (the latter being more of a concern). Treachery! Seek it out! He’s calling for help, for the guards to come, pressing the biggest panic button, the one labelled treason. And while the SD is editorial, it makes sense for Osric to be the one to leave, either to raise the alarm, or else making himself scarce because he knows or suspects too much.

But it’s Laertes who has to make the terrible announcement, perhaps as Claudius tends to Gertrude, apparently full of concern: it—treachery—is here, Hamlet, thou art slain. You’re as good as dead, right now. No medicine in the world can do thee good. No antidote, no help. And it’ll be very, very fast: in thee there is not half an hour’s life. You’ve had it, the clock’s ticking. The treacherous instrument is in thy hand unbated and envenomed. Look, you’re holding it right now, that rapier, its point sharp and unprotected, and poisoned too. (The un- and en- are so neat, so economical, such tiny details, the one prefix denoting the absence of the thing that should be there, the other the presence of the thing that shouldn’t.) And—Laertes must shudderingly reveal—the foul practice hath turned itself on me. I’m caught in my own trap, and practice here is more than an action, it’s deception, conspiracy. I am the biter bit. Lo, here I lie, never to rise again. I’m done for; I’ve caused my own death too. And he’s going fast (will this also be Hamlet’s fate, so quick?)—he’s got to confess, to explain as much as possible in as few words as possible: thy mother’s poisoned (just to confirm)—I can no more, he’s gasping, sinking—the King, the King’s to blame. It’s all his fault. All of it. Does Claudius turn, horrified, start to protest—he’s clearly out of his mind, doesn’t know what he’s saying, poor chap—but the game’s up, for everyone, Hamlet included. The King’s to blame, for everything.