chunk: The prisoner king is then taken to Berkeley Castle, where he meets the luxuriously cruel Lightborn, whose name is an anglicised version of "Lucifer". Despite knowing that Lightborn is there to kill him, Edward asks him to stay by his side. Lightborn, realizing that the king will not fall for deception, kills him. Maltravers and Gurney witness this before Gurney kills Lightborn to keep his silence. Later, however, Gurney flees, and Mortimer sends Maltravers after him, as they fear betrayal. Isabella arrives to warn Mortimer that Edward III, her son with Edward II, has discovered their plot. Before they can plan accordingly, her son arrives with attendants and other lords, accusing Mortimer of murder. Mortimer denies this, but eventually is arrested and taken away. He tells Isabella not to weep for him, and the queen begs her son to show Mortimer mercy, but he refuses. Edward III then orders Mortimer's death and his mother's imprisonment, and the play ends with him taking the throne.