When did Macbeth kill Duncan's chamberlains?

Question

In Macbeth, at the end of Act 2, Scene 3 Macbeth reveals that he killed Duncan's servants:

O, Yet I do repent me of fury
That I did kill them

However, doesn't this appear as a plot hole when we take Lady Macbeth's reaction into account ("Help me hence, ho!")?

I see two interpretations:

1. Macbeth killed the servants when he murdered Duncan. However, as we see later in the play that Lady Macbeth has no capacity to actually murder Duncan ("Had he not resembled my father as he slept, I had done't"). So, in my opinion, there is absolutely no chance Lady Macbeth wouldn't have noticed the murdered chamberlains and not say anything to Macbeth about it when she returns after marking them with blood (even if they were under stupor from the alcohol, seeing whether someone is dead or alive is not very difficult) so this seem improbable in my view.

2. Macbeth murdered the chamberlains after Macduff reports the king has been murdered. This can't be possible since Lennox went with him (presumably, "Exeunt Macbeth and Lennox" II.3.72) and murdering the servants in front of a nobleman is likely to elicit some reaction in the very least from Lennox in the confrontation - but he does not mention it; nor are we given any hints as to whether Lennox supported Macbeth (if any, he leads the army against him later on).

So the way it looks to me, this appears as a plothole. Or is there something I am missing here?

Answer 1

Option 2 is correct: Macbeth killed the chamberlains during act II scene 3, where the sequence of events is as follows:

1. Macduff goes to visit Duncan in his chamber.

   Macduff. I’ll make so bold to call.
   For ’tis my limited service.

   Exit Macduff.

2. Macduff returns and reports that he found Duncan murdered.

   Enter Macduff.

   Macduff. O horror, horror, horror!
   Tongue nor heart cannot conceive nor name thee!

3. Macbeth and Lennox go to see for themselves.

   Macduff. Approach the chamber, and destroy your sight
   With a new Gorgon. Do not bid me speak.
   See, and then speak yourselves.

   Exeunt Macbeth and Lennox.

4. Macbeth and Lennox come back (with Ross, whom we can suppose has been woken by the commotion) and report the killing of the chamberlains.

   Enter Macbeth and Lennox with Ross.

   […]

   Lennox. Those of his chamber, as it seem’d, had done’t:
   Their hands and faces were all badg’d with blood;
   So were their daggers, which, unwip’d, we found
   Upon their pillows. They star’d, and were distracted;
   No man’s life was to be trusted with them.

   Macbeth. O, yet I do repent me of my fury,
   That I did kill them.

We have no reason to suspect Lennox of complicity with the murder plot, therefore no reason to doubt what he says here, which is that the chamberlains “stared, and were distracted”, which they could not have done if Macbeth had killed them at the same time as Duncan. This rules out option 1, that Macbeth killed the chamberlains at the same time as Duncan.

So we are left with the difficulty of explaining Lennox’s reaction. Macbeth has just killed the chamberlains in front of him: how can Lennox accept this? But if this is a difficulty with respect to Lennox, it’s a difficulty with respect to everyone else in the scene too: that is, to Macduff, Ross, Banquo, Donalbain, and Malcolm. Why don’t they complain about Macbeth’s bloody act of (supposed) revenge? Why don’t they call the police to have Macbeth arrested?

We have to conclude, from the way they act and react, that the characters are living in a society of armed warriors for whom violent extrajudical retribution is customary and, within limits, acceptable. You can see that Lennox says that “No man’s life was to be trusted with [the chamberlains]” and so it seems that even if he does not approve, he accepts Macbeth’s action as a kind of vigilante execution.

Answer 2

TL;DR

There is no plot hole here. Macbeth killed the chamberlains in Act 2, scene 3, when the murder of King Duncan is discovered. Critics debate whether Lady Macbeth's fainting is feigned or real.

Deets

In Act 2, scene 2, Macbeth tells his wife after returning from Duncan's chamber about how the two chamberlains woke each other after one cried "murder" in his sleep. He adds,

One cried 'God bless us!' and 'Amen' the other;
As they had seen me with these hangman's hands.
Listening their fear, I could not say 'Amen,'
When they did say 'God bless us!'

The "hangman's hands" are his bloody hands after killing Duncan. His guilt about killing Duncan is why he cannot say, "Amen". There is nothing in the remainder of the scene that suggests Macbeth killed the chamberlains after listening to their prayers; he already seemed sufficiently shaken with guilt after killing Duncan.

In Act 2, scene 3 he comes back from Duncan's room saying,

O, yet I do repent me of my fury,
That I did kill them.

This can only mean that he killed them after "discovering" Duncan's death. First, Lady Macbeth's plan of plying the chamberlains with liquor and wiping the bloody daggers on them seemed sufficient. Killing the chamberlains was never mentioned in that plan. Second, if the chamberlains had been dead when Duncan's body was found in the morning, Macbeth's confession that he killed the servants would raise the question why he was in Duncan's chamber without immediately rousing the entire castle about the king's death. The murder of the chamberlains seems improvised and intended to prevent the denial of their guilt.

Macduff does actually question Macbeth—who had been curiously eloquent throughout the whole scene, more eloquent than enraged about the murder—on why he killed them. Lady Macbeth faints in the middle of her husband's explanation and critics still debate whether this was intended as a ruse to draw attention away from Macbeth (Hunter, page 156; Bate & Rasmussen, page 51).

For example, Trevor Nunn, director of the famous 1976 RSC production of Macbeth (with Ian McKellen and Judi Dench),

made it clear [in the 1976 production] that her 'fainting' was a vitally necessary device to prevent the questioning of her husband from going further. [Bate & Rasmussen, page 158]

References

• Shakespeare: Macbeth. Edited by G. K. Hunter. New Penguin Shakespeare, 1967.
• Shakespeare: Macbeth. Edited by Jonathan Bate and Eric Rasmussen. The RSC Shakespeare. Macmillan, 2009.