How is foreshadowing used in the motion picture, Notorious?

Walter Beardsley works with Devlin and Prescott, and he considers Alicia to have a loose reputation with men, which he seeks to exploit. Although Alicia is not in the room, Devlin quickly and vehemently corrects Beardsley. Beardsley's derogatory comment concerning Alicia's reputation foreshadows Devlin's true, intense feelings for Alicia.