At Macbeth's castle
Banquo, Fleance, Macbeth, random servant.
Midnight and for one reason or another no one is sleeping. Banquo can't stop thinking about the witches. Macbeth launches into a long monologue. "Is this a dagger which I see before me". He is contemplating the murder of the king and death in general.
Again at Macbeth's castle
Lady Macbeth, Macbeth
After Lady Macbeth hears some freaky sounds of the night Macbeth enters and says he has killed the king. It would seem that someone has witnessed the murder. Macbeth gets cold feet so Lady Macbeth goes to kill the witness.
Still at the castle
A porter, Macduff, Lennox, Macbeth, Lady Macbeth, Ross, Malcolm, Donalbain
The porter opens the gate for Macduff and Lennox. All the knocking at the gate woke up Macbeth. Macduff, Lennox, and Macbeth enter the king's chamber to find that his throat has been sliced (Macbeth's handy work). An alarm is raise and the whole castle wakes and hears the news. The king's court was also found dead and Macbeth claims credit saying that they were the murderers and he killed them for revenge. Malcolm and Donalbain do not reveal the truth. Malcolm and Donalbain flee to England and Ireland respectively.
OUTSIDE the castle this time
Ross, old man, Macduff,
Ross and man talk of a time past and the murder. It seems that people believe that Macbeth killed the killers. People also suspect Malcolm and Donalbain (the king's sons) since the have since fled.