Innovative evidence leads the team to discover a crucial element in the case has gone missing. Kreizler (Daniel Brühl) and Moore (Luke Evans) interview a witness to find out what happened to Moore at the Brothel. Sara (Dakota Fanning) attempts to live in a world outside the investigation. Kreizler challenges them to look within themselves. 
- Dr. Kreizler: "Why does our killer do what he does?"
- Sara Howard: "This is evidence of corruption within the police department."
- Stevie Taggert: "There has been another one."
- Dr. Kreizler: "They have been led to slaughter."
- John Moore: "Kreizler, that's quite enough!"
- The episode covers from Chapter Twelve to Chapter Fifteen of Caleb Carr's novel, concluding the First Part and starting the Second Part. As with previous episodes, changes in adaptation have been made.
- The episode title is a reference to the nickname of John Moore's potential suspect.