Zach Braff Dr. John "J.D." Dorian Actor Sarah Chalke Dr. Elliott Reid Actor Donald Faison Dr. Chris Turk Actor John C. McGinley Dr. Perry Cox Actor Judy Reyes Nurse Carla Espinosa Actor Ken Jenkins Dr. Bob Kelso Actor Neil Flynn The Janitor Actor Mandy Moore Julie Guest Star Billy Dee Williams Billy Dee Williams Guest Star Jay Kenneth Johnson Dr. Matthews Guest Star Christa Miller Jordan Sullivan Guest Star Michael Learned Mrs. Wilk Guest Star Yvonne Arias Nurse Martinez Guest Star Becca Battoe Nurse Guest Star Frank Cameron Dr. Mickhead Guest Star Stacey Hinnen Mr. Morgan Guest Star Erica O'Keith Whitney Guest Star Scott Rabideau Orderly Guest Star Eamonn Roche Buzz Clark Guest Star Bill Lawrence Executive Producer Chris Koch Director Mike Schwartz Writer