Grey's Anatomy season 18 is officially happening on ABC. The network renewed the medical drama for another installment and Ellen Pompeo, who plays Meredith Grey and serves as a producer, also closed another one-year deal. Hence, there is no need to worry about the future of the series.

Now, one of the questions entering Grey's Anatomy season 18 is whether or not other original cast members are coming back. In season 17, some of the characters, who have been long dead, showed up in Meredith's dream beach sequence.

Pompeo's character reunited with her late husband Derek Shepherd (Patrick Dempsey), her late friend T.R. Knight (George O'Malley), and late sister Lexie Grey (Chyler Leigh). This time, fans were hoping that Meredith will reunite with others -- especially those who moved somewhere else.

For instance, there have been hopes that Sandra Oh will reprise her role as Cristina Yang in Grey's Anatomy season 18. The character is one of the closest friends of Meredith, but she departed from the series after season 10. She leaves for Zurich and now owns a research hospital.

But, even though Cristina has not been seen in the series over the past years, she was frequently mentioned by some characters. She's still part of Meredith's life, especially since they have been through tough times together and shared a lot of moments.

So, is there a chance for Oh returning as Cristina in Grey's Anatomy season 18? It looks like the actress has no current plans to reprise her role in the medical drama. This is something that she during an interview with Los Angeles Times' Asian Enough podcast.

Oh said that she left the series about seven years ago and explained that in her mind, "it's gone." For a lot of viewers, they're still looking forward to seeing Cristina at some point. However, the actress made it clear that she had already "moved on."

Oh is committed to other projects at the moment, with BBC's Killing Eve being the biggest one. It might be hard to balance her schedule in the medical drama and comedy spy-thriller drama. Everything may depend on the schedule since both series weren't filmed in the same location.

Meanwhile, Grey's Anatomy season 18 release date hasn't been set. The current installment is still airing, so production may not begin anytime soon. The cast and crew need to take a break after the season 17 finale, which means the filming could start before 2021 ends.