New York City. 1896. The heart of America’s Gilded Age. When a young boy prostitute is found butchered on the unfinished Williamsburg Bridge, an alienist named Laszlo Kreizler, a newspaper illustrator by the name of John Moore, a secretary, Sara Howard and a police commissioner named Theodore Roosevelt begin an investigation outside the law to find the serial killer.
Sara finds a clue and Kreizler tries to connect the evidence left behind by the serial killer. Kreizler takes Moore, Sara, Marcus and Lucius to Delmonico's in New York and informs them they're working together to catch the killer.
Innovative evidence leads the team to discover a crucial element in the case has gone missing. Kreizler and Moore interview a witness to find out what happened to Moore at the Brothel. Sara attempts to live in a world outside the investigation. Kreizler challenges them to look within themselves.
Kreizler and Sara discuss the capacity to kill. Moore goes on a date. Byrnes and Captain Connor keep an eye on a potential suspect. Roosevelt finds himself under public scrutiny.
The team learns more about the killer. Moore and Sara share an intimate moment. Kreizler seeks advice from an old mentor. Roosevelt takes action.
The team hatches a plan to catch the killer. Moore checks in on a friend. Kreizler faces his own self-doubt about the investigation. Roosevelt attends an event with the city’s elite. Sara looks into Kreizler’s past. Connor acts on impulse.
Kreizler and Moore follow a lead. Sara visits a hospital and is forced to confront her past. Cyrus, Kreizler’s carriage driver, recovers from his injuries. Byrnes and Connor plot against the team.
Kreizler and Moore travel to Washington D.C., Sara goes rogue in pursuit of the truth. Lucius tells Marcus a secret. Byrnes and Connor tighten their grip on the investigation.
Kreizler mourns the loss of a friend. Sara pushes the team to forge ahead. Moore warns his friend the killer will strike again. Cyrus seeks revenge.