On screen
Cast
86 credited performers
Michael Chernus
John Wayne Gacy
Gabriel Luna
Det. Rafael Tovar
James Badge Dale
Chief of Detectives Joe Kozenczak
Michael Angarano
Sam Amirante
Chris Sullivan
Lead Prosecutor Bill Kunkle
Marin Ireland
Elizabeth Piest
Greg Bryk
Harold Piest
Cricket Brown
Kerry Piest
Ted Dykstra
Det. Allen Fanholm
Thom Nyhuus
Kenneth Piest
Jake Horowitz
David Cram
Hamish Allan-Headley
Det. Michael Albrecht
Nina Kiri
Mary Amirante
Chloe Avakian
Patti Szyc
Sprague Grayden
Bessie Stapleton
Krista Bridges
Rosemarie Szyc
Michael Esper
Bob Motta
Augustus Prew
Jeffrey
Etienne Kellici
Samuel Stapleton
Mason Versaw
Robert Donnelly
Alex Paxton-Beesley
Helen
Eva Foote
Carol Gacy
Kristine Nielsen
Marion Gacy
Lena Pepe
Juanita
Christian Bako
Marko Butkovich
Jim Annan
Judge Louis Garippo
Mallory Bechtel
Mary Jane
Ryker Baloun
Robert Piest
Finlay Wojtak-Hissong
Randy Reffett
Robert Meynell
Donald Voorhees Sr.
Andrew Johnston
Donald Voorhees Jr
Joshua Kilimnik
Teenage Gacy
Max Mattern
Billy Carroll
Brayden Raqueño
Dale Landingin
Lynne Griffin
Gladys
Desmond Sivan
Fred Tovar
Levi Shelton
John 'Johnny' Szyc
Tom Barnett
Richard Szyc
Mitchell Court
Eldest Szyc Son
Yona Epstein-Roth
Cliff
Rolando Alvarez Giacoman
Janitor
Megan Murphy
Lynn Meadows
Mary Wiseman
Karen Gacy
Dan Lett
Dr. Stein
Samantha Adams
Marlynn Gacy
Brenda Bazinet
Eugenia Godzik
Jessie Behan
Young Marion Gacy
Kathryn Bellamy
Beth
Quincy Tyler Bernstine
Dr. Healy
Alec Dahmer
Rookie Cop
Colton Ryan
Billy Kindred
Nigel Shawn Williams
John Davis
Ianne Fields Stewart
Sophia St. Laurent
Ish Morris
Guard Jenkins
Lizzie Moffatt
Young Woman 1
Aidan Pinsler
Young Male
Amanda Cheung
Hot Girl
Matthew Chiarelli
Delivery Man 1
Mira Skye Korngold
Waitress
Sam Wexler
Delivery Man 2
Gavin Lewis
Timothy McCoy
Crede Cooper
John Butkovich
Thomas Mitchell Barnet
Phil Torf
Alexander Crowther
Detective Janus
Christopher Jacot
Detective Everford
Jarrod Vanvolkenburg
Jerry Latherow
Aidan Wojtak-Hissong
Randy Reffett
Cameron Brodeur
Michael Rossi
Brandon McEwan
Philip Paske
Luke Humphrey
Terry Sullivan
Aidan Gouveia
Greg Godzik
Rayisa Kondracki
Geraldine
Daniel Griffin
Charlie Reynolds
Dwight Ireland
Press Conference Reporter
E. Fegan DeCordova
Reporter
Karrie Kwong
Reporter
Ella Rae Peck
Rose Perino
R Austin Ball
Ron Dovenek
Morgan Kelly
Fred Richman
Dylan Taylor
CPD Officer O'Neal
Lauren Collins
Genie Godzik
Kylee Evans
Deanna Amirante
Marcia Bennett
Delores Nieder
Eric Wiegand
Danny Jockell
Abigail Nicholson
Girl with Acid
Igby Rigney
Phil