Stephen Norton and Margaret Litchfield

Stephen Norton and Margaret Litchfield are connected through one of Norton’s earlier crimes: he befriends the Litchfield family and encourages Margaret to imagine herself as a heroine who could rescue her sisters from their life of confinement by causing their father’s death. Poirot later identifies Norton as the actual killer and argues that Margaret would not have acted without his influence, recasting her apparent guilt as the result of deliberate psychological manipulation.

The Litchfield family and Norton’s influence

Norton’s method depends on finding a desire or belief already present in another person and intensifying it rather than introducing an entirely new impulse. In Margaret’s case, he plays upon her half-formed conviction that her elderly aunt’s death would be a release for the aunt and bring Margaret financial ease. Separately, as a friend of the Litchfields, he encourages Margaret to see herself as a heroine delivering her sisters from what she regards as a life sentence of imprisonment. Poirot presents this suggestion as the seed on which Norton’s influence could work: Margaret’s sense of rescue gives a potentially criminal act a seemingly benevolent purpose.

Margaret as an instrument of the crime

Poirot’s retrospective account places Margaret among the people Norton used to enact crimes while remaining outside suspicion. He insists that the victims and apparent perpetrators were not simply acting alone: Norton applied psychological pressure to an existing weakness or conviction until another person might cross a boundary they would otherwise have resisted. In Margaret’s case, this means that her apparent role in her father’s death does not make her the killer. Poirot’s conclusion is that Norton killed her father, while Margaret was the person whose thinking he had influenced.

Revelation and aftermath

The connection becomes explicit in Poirot’s final message to Arthur Hastings, in which he asks Hastings to find Elizabeth Cole, also known as Elizabeth Litchfield, and tell her that her father was killed not by Margaret but by Norton, the seemingly sympathetic family friend. Poirot believes Elizabeth has continued to suffer because she thinks her sister was responsible. By explaining that Norton was the true killer and that Margaret had no watchful investigator to protect her from his influence, Hastings can help remove that burden of guilt. The relationship thus reaches beyond Norton’s manipulation of Margaret: its lasting consequence is the anguish borne by her sister, and Poirot’s effort to correct the story Elizabeth has believed.