S1·E3 – Horrific Acts

John Wayne Gacy

Self (archive footage)

Robert K. Ressler

Self - Ret. FBI Profiler (archive footage)

Terry Sullivan

Self - Fmr. Prosecutor, Cook County, IL

Jay Levine

Self - Ret. News Anchor & Chief Correspondent

David Hachmeister

Self - Ret. Des Plaines Police Officer

Rafael Tovar

Self - Ret. Des Plaines Police Detective

Lawrence Finder

Self - Fmr. Prosecutor, Cook County, IL

Michael Albrecht

Self - Ret. Des Plaines Police Officer

Karen Kuzma

Self - John Gacy's Sister

William Kunkle

Self - Fmr. Chief Prosecutor, Cook County, IL

Patti Szyc-Rich

Self - John Szyc's Sister

Jim Szyc

Self - John Szyc's Brother