Lady Macbeth persists in trying to wash an imagined bloodstain from her hands, saying "Out, damned spot! Out, I say!" She is reliving the murder of Duncan over and over, hearing bells and seeing sights from that night. She switches between addressing an imagined bloodstain and chiding an imagined Macbeth for his fear. Her words reveal that she is now terrified herself of everything. The doctor recognizes the significance of her words, as she has now confessed details about Duncan's murder.