Jake Gyllenhaal
Robert Graysmith
Mark Ruffalo
David Toschi
Anthony Edwards
William Armstrong
Robert Downey Jr.
Paul Avery
Chloë Sevigny
Melanie
Elias Koteas
Jack Mulanax
John Carroll Lynch
Arthur Leigh Allen
Brian Cox
Melvin Belli
Dermot Mulroney
Martin Lee
Charles Fleischer
Bob Vaughn
Zach Grenier
Mel Nicolai
Philip Baker Hall
Sherwood Morrill
James Le Gros
George Bawart
Donal Logue
Ken Narlow
Richmond Arquette
Zodiac 1 / Zodiac 2
Bob Stephenson
Zodiac 3
John Lacy
Zodiac 4
Ed Setrakian
Al Hyman
John Getz
Templeton Peck
John Terry
Charles Thieriot
Candy Clark
Carol Fisher
June Diane Raphael
Mrs. Toschi
Ciara Hughes
Darlene Ferrin
Lee Norris
Young Mike Mageau
Patrick Scott Lewis
Bryan Hartnell
Pell James
Cecilia Shepard
David Lee Smith
Father
Jason Wiles
Lab Tech Dagitz
Charles Schneider
Cabbie / Paul Stine
James Carraway
Shorty
Tom Verica
Jim Dunbar
Jimmi Simpson
Mike Mageau
Doan Ly
Belli's Housekeeper
Karina Logue
Woman
Joel Bissonnette
Inspector Kracke
John Mahon
Riverside Captain
Matt Winston
John Allen
Jules Bruff
Catherine Allen
John Ennis
Terry Pascoe
J. Patrick McCormack
Police Commissioner
Adam Goldberg
Duffy Jennings
Clea DuVall
Linda del Buono
Paul Schulze
Sandy Panzarella
Adam Trese
Detective #1
Penny Wallace
Mulanax's Secretary
John Hemphill
Donald Cheney
Michel Francoeur
Man on Marquee
Thomas Kopache
Copy Editor #1
Barry Livingston
Copy Editor #3
Christopher John Fields
Copy Editor #4
Jack Samson
Young David Graysmith
Micah Sauers
David Graysmith
Zachary Sauers
Aaron Graysmith
Jessica Baltutis
Margot Graysmith
Peter Quartaroli
Patrolman Fouke
Geoff Callan
Patrolman Zelms
Michael Hungerford
Truck Driver
Anna Katarina
Society Woman
E.P. McKnight
Informant (Hall of Justice A)
Betty Murphy
Informant
Jeff Daniel Phillips
Informant
Shane Woodson
Informant
Cookie Crawford
Informant #8
Cassius M. Willis
Uniform Cop
Judith Drake
Florence Douglas
Phoebe Holston
Prison Guard
Marty Lodge
Pinole Foreman
Cooper Thornton
Internal Affairs Agent #1
Cazimir Milostan
Internal Affairs Agent #2
Charlotte Ferguson
Kathleen Johns' baby
Phoebe Ferguson
Kathleen Johns' baby
Kacey Malmsten
Kathleen Johns' baby
Karly Malmsten
Kathleen Johns' baby
JD Cullum
Director
Stanley B. Herman
Staff Editor
Roy Lee Jones
Distraught African American Male
Michael Rose
Navy Project Leader
James Joseph O'Neil
DOD Project Leader
Rod Damer
FBI Codebreaker
John Sarno
Donald Harden
Gloria Grant
Bettye Harden
Brett Rickaby
Detective Roy
M.F. Bernier
Detective #2
Carter Evans
Newscaster #2
Bill Seward
TV News Anchor
Dave Nemeth
Newscaster #4
Ted Garcia
Anchorman #1
Greg Wolf
Interviewer #1
Barry LeBrock
Reporter
Ione Skye
Kathleen Johns (uncredited)
David Winston Barge
Vallejo Desk Ofiicer (uncredited)
Hayati Akbas
Hardware Store Customer (uncredited)
Brad Carr
Camera Man (uncredited)
Mitchell Fink
Reporter (uncredited)
Erica Ford
Traveler (uncredited)
Tish Hicks
Informant (uncredited)
Danielle McKee
Prisoner (uncredited)
Derris Nile
Office Worker (uncredited)
Carmen Plumb
Janie (uncredited)
Callie Thompson
Child Witness (uncredited)
Bud Davis
Patrolman (uncredited)