Macduff leaves scotland and his wife isn’t happy with this as he didn’t inform her he’d be doing so. She feels betrayed by him. One of the muderes also arrive on stage. They were told by Macbeth to kill Macduff and his family. The murderer only manages to kill one of the family members, Macduffs son.
“I have done no harm. But I remember now I am in this earthly world, where to do harms often laudable” Said by Lady Macduff, she means that even though she hasn’t done anything of harms way, her husband has therefore she will also pay for the crimes of what he as done.