She is [[imagining]] blood on her hands and is re-living the night of [[Duncans]] death. Shakespeare uses [[hyperpole]] again when Lady Macbeth states that all the [[perfumes]] of Arabia will not remove the [[smell]] of blood from her hands. The doctor states that her [[condition]] is not physical but she needs [[spiritual]] help instead and they should not [[repeat]] what they have heard.
This scene opens with a [[gentlewoman]] and a [[doctor]] discussing Lady Macbeth's mental [[decline]]. They discuss that Lady Macbeth has been [[sleepwalking]] and talking about past [[deeds]]. Lady Macbeth then arrives and is holding a [[candle]] and sleepwalking. The gentlewoman states that she has [[requested]] that she needs a light at all times through the night. Lady Macbeth begins to say [[Out damned spot!]] when [[washing]] her hands.