Delores Marsh was the lady that Samuel Cavanagh used as a diversion whilst he and his friend Charles Wyler smuggled his wife's body out of his building. The body would eventually turn up on a building site, and set the ball rolling on A Chill Goes Through Her Veins. Living alone, she was understandably disinclined to let people into her apartment, and conducted her whole discussion with Beckett and Castle with the chain on her door, looking through the gap.