Dr. Parker: “a top-of-his-game physician in his 40s or 50s” Dr. Mel Barnett: “slightly younger” doctor. According to an ABC press release about the Season 9 premiere, he is played by Philip Casnoff. Male medical professional: “smart,” “not Hollywood handsome” Female medical professional: “smart,” “not Hollywood pretty” Female patient: “girl-next-door pretty” Another doctor: A mid-40s male doc who's a "genuinely good guy" and will be in more than one episode.
And these are the actors who have confirmed roles in the new season:
Gaius Charles has an as-yet undescribed recurring role. According to a press release about the Season 9 premiere, he is playing a character named "Shane."
Steven Culp has a recurring role as a "top dog doctor," though whether he'll work at Seattle Grace-Mercy West or elsewhere is not yet known. According to the Season 9 premiere press release, he plays Dr. Parker.