: Now the lead of the investigation, she navigates the challenges of being a female detective in a male-dominated society while grappling with the guilt of Martha Napp's death.

The episode sets a dark, atmospheric tone, highlighting the stark inequalities and institutional corruption of late 19th-century New York. It introduces the central antagonist of the season, , and explores the "Angel of Darkness" motif—a killer who targets the most vulnerable.

The season opens with , who has fulfilled her ambition of opening her own private detective agency. She is initially occupied with the case of Martha Napp, a woman sentenced to death for the alleged murder of her own child. Despite the efforts of Sara, Kreizler, and John to secure a stay of execution from Teddy Roosevelt, they fail, and Martha is executed.

: Transitioned from a newspaper illustrator to a reporter for the New York Times . He is now engaged to Violet Hayward, adding a layer of personal tension to his reunion with Sara.