 Joaquin PhoenixArthur Fleck | Arthur Fleck |
 Lady GagaLee Quinzel | Lee Quinzel |
 Brendan GleesonJackie Sullivan | Jackie Sullivan |
 Catherine KeenerMaryanne Stewart | Maryanne Stewart |
 Zazie BeetzSophie Dumond | Sophie Dumond |
 Steve CooganPaddy Meyers | Paddy Meyers |
 Harry LawteyHarvey Dent | Harvey Dent |
 Leigh GillGary Puddles | Gary Puddles |
 Ken LeungDr. Victor Liu | Dr. Victor Liu |
 Jacob LoflandRicky Meline | Ricky Meline |
 Bill SmitrovichJudge Herman Rothwax | Judge Herman Rothwax |
 Sharon WashingtonDebra Kane | Debra Kane |
 Alfred Rubin ThompsonErnie Bullock | Ernie Bullock |
 Connor StorrieYoung Inmate | Young Inmate |
 Gregg DanielMusic Teacher | Music Teacher |
 Mac BrandtArkham Guard | Arkham Guard |
 George CarrollArkham Guard | Arkham Guard |
 John LacyArkham Guard | Arkham Guard |
 Tim DillonArkham Guard | Arkham Guard |
 Wayne DehartE Ward Inmate | E Ward Inmate |
| TTroy FrominE Ward Inmate | E Ward Inmate |
| AAjgie KirklandE Ward Inmate | E Ward Inmate |
| TTerrance T.P. PoliteE Ward Inmate | E Ward Inmate |
 Jimmy Walker Jr.E Ward Inmate | E Ward Inmate |
 Toney WilsonE Ward Inmate | E Ward Inmate |
 June CarrylDr. Louise Beatty | Dr. Louise Beatty |
 Don McManusPaddy Meyers' Producer | Paddy Meyers' Producer |
 G.L. McQuearyHead Bailiff | Head Bailiff |
 Angela D. WatsonJury Foreman | Jury Foreman |
 Murphy GuyerWhite Chapel Minister | White Chapel Minister |
