Elmer Wayne Henley, Jr.

Elmer Wayne Henley Jr. is a young man serving time for his part in a string of murders in Houston, sought out by Holden Ford as one more subject for the FBI's study of extreme violence. He is soft-spoken, watchful, and eager to explain himself, framing his own history with a calm, almost helpful precision.

Robert Aramayo plays him as disarmingly ordinary — polite, boyish, quick to smile — which is precisely what makes the interview scenes so unsettling. The writing lets him narrate horror in the even tone of someone recounting a job, and Aramayo never signals monstrousness, forcing the viewer to sit with how easily it hides in plainness.