Main • Ken Jeong as Dr. Kendrick "Ken" Park. Ken is a constantly-joking, narcissistic, sometimes-thoughtless general practitioner employed at Welltopia Medical Group. He loves his family and coworkers but is often oblivious to their feelings. He has a younger sister, Dr. Wendi (Margaret Cho), of whom he is jealous. • Suzy Nakamura as Dr. Allison Park (née Kuramata). (season 1). Julie is Ken's protege and a trained doctor, although she is unsure of herself. She speaks in a nervous, high-pitched voice and is referred to as "fragile" by both herself and coworkers. She has a tendency to keep on talking when she's nervous, divulging Ken's secrets. She is an extremely thorough worker, to the point of spending three hours with a patient. On the season 2 premiere, it was revealed that she left the hospital to do a medical internship elsewhere. • Dave Foley as Pat Hein. • Mehmet Oz as himself • Will Yun Lee as Dr. Kevin O'Connell • Joel McHale as Ross • Danny Pudi as Topher • Jim Rash as Devon Drake • Stephen Tobolowsky as Joe • Ian Chen as Henry • Randall Park as Gary Chon • James Urbaniak as James Miller • George Wyner as Dicky Wexler • Jeff Ross as Doug • Betsy Sodaro as Sonja • Gillian Jacobs as Erin • Yvette Nicole Brown as Amy • Rhys Darby as Charles Evans • Jonathan Banks as Dr. Erwin • Dan Harmon as himself • Alison Brie as herself ==Episodes==