"Mademoiselle, I beseech you, do not do what you are doing." "Leave dear Linnet alone, you mean!" "It is deeper than that. Do not open your heart to evil." Her lips fell apart; a look of bewilderment came into her eyes. Poirot went on gravely: "Because--if you do--evil will come...Yes, very surely evil will come...It will enter in and make its home within you, and after a little while it will no longer be possible to drive it out." --