There are seven main characters in seasons one-eight, Zack Braff (J.D), Sarah Chalke (Elliot Reid), Donald Faison (Turk). Neil Flynn (Janitor), Ken Jenkins (Bob Kelso). John C. McGinley (Perry Cox), and Judy Reyes (Carla Espinosa). The ninth season the actors are Eliza Coupe (Denise Mahoney), Kerry Bishe (Lucy Bennett), Michael Mosley (Drew Suffin), and Dave Franco (Cole Aaronson). From the original cast that are in season nine Zach Braff (J.D), John C. McGinley (Perry Cox), and Donald Faison (Turk).