Heigl last appeared on the show in Season 6 and told ET in July that she didn’t know if she “would or if [she] wouldn’t” return. But you have to admit, bringing her back just as Alex (Justin Chambers) and Jo (Camilla Luddington) are dealing with some things would complicate matters, just because of Izzie’s history with him.
Isaiah Washington (Preston Burke)
Washington reprised his character when the series prepared to say goodbye to Cristina. While it’s hard to imagine what could bring him back, we can’t rule out the possibility since he’s already been back once since his exit.
Kate Walsh (Addison Montgomery)
Addison has returned for medical cases in the past, so it’s not hard to imagine that happening again. It could also be interesting to see her reaction to Meredith’s relationship with DeLuca (Giacomo Gianniotti).
Jessica Capshaw (Arizona Robbins)
Arizona left at the end of Season 14 to move to New York with her daughter Sofia, and there was potential for a rekindling of her romance with Callie (Sara Ramirez) as well. It wouldn’t be difficult to imagine a medical case — one that hits close to home or not — that would necessitate Arizona’s presence at the hospital.
Sarah Drew (April Kepner)
Considering April is still in Seattle and has a child with Jackson (Jesse Williams), it wouldn’t even be a stretch in-show for her to make an appearance. And if you factor in the cliffhanger involving Jackson and the fact that Williams “will likely do a limited number of episodes” of Season 16 due to a Broadway role, there could easily be a storyline that brings April back in the fold.
Sara Ramirez (Callie Torres)
Ramirez isn’t returning to Madam Secretary as a series regular for its final season, so that takes care of one potential roadblock. Callie could easily return to Seattle for a professional or personal reason, with or without Sofia and/or Arizona, depending on their relationship status.
But will the new relationship be as successful as Bailey and Ben's?
Over its 15 seasons (so far), Grey's has had quite a few doctors come and go, so there's a big pool of possibilities. However, while a character who has died has returned before, we're going to rule that out in this case.
Click through the gallery above to see some of the possible candidates for a return, from least to most likely.
Grey's Anatomy, Season 16 Premiere, Thursday, September 26, 8/7c, ABC