ATTORI:

• 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))