Grey's Anatomy is a show that is constantly revolving. Because of its ability to change and morph given its revolving cast, the medical drama is still going strong into its whopping 14th season on ABC. Grey's will certainly go through some changes with its upcoming finale, as two long time cast members are departing the show: Sarah Drew (April Kepner) and Jessica Capshaw (Arizona Robbins). The latter has been on the show for ten seasons, so the pressure is on for the writers to craft a believable and satisfying conclusion to Arizona's story. News just dropped that guest star Geena Davis is returning to Grey's, which can't be a coincidence.
News recently broke (via Deadline) that the Oscar nominee would be returning to Grey's Anatomy as her character Dr. Nicole Herman. Herman was last seen back in Season 11, where she served as Arizona's mentor in fetal surgery. Herman taught Arizona everything she knew because of her own failing health, with Amelia eventually able to save the surgeons life-- although she lost her sight in the process.
If Dr. Herman is returning to Grey Sloan Memorial Hospital, it's likely one for one reason: to recruit Arizona onto some project. She trained to Arizona to be just as strong a surgeon as she, and will likely need Robbins in order to continue her work. Since Arizona doesn't have a ton tying herself to Seattle, this could be the opportunity for her to be written off the show.
This wouldn't be the first time that a major Grey's Anatomy character departed the show for professional reasons. Most notably Sandra Oh's Cristina Yand moved to Switzerland to run her own hospital and continue her groundbreaking cardio work. The ambition of the surgeons is one of the main cruxes of the show, so it would be great to see Arizona leave in order to take her career to the next level. Considering how many characters have been killed off or nearly died before departing, it's refreshing to have the stakes be a bit lower.
Geena Davis appeared in 12 episodes as Dr. Herman during her time on Grey's Anatomy, and the character's disappearance always felt a bit disjointed. The last we heard, she was learning how to live her life without sight. But following one quick reference, she was never seen or heard from again.
Showrunner Krista Vernoff seem to enjoy bringing back characters from Grey's Anatomy past, which has been a fun aspect of watching for the OG fans out there. This season brought back Teddy Altman, and recently saw the return of April's ex-fiancee Matthew. Matthew and Dr. Herman's reprisals will no doubt give the two departing surgeons logical and emotional motivation to leave the show, which is something Grey's certainly owes the two actresses.