'Grey's Anatomy' Reveals Another Major Return in Season 17: Who Could It Be?

Is it George? Is it Lexie? Is it Ellis? It's going to be a long two weeks.

McDreamy wasn't the only Grey's Anatomy surprise.

With Meredith Grey's (Ellen Pompeo) bout with coronavirus worsening by the minute, the next episode, titled "You'll Never Walk Alone," reveals that Derek Shepherd (Patrick Dempsey) isn't the only one from her past to pay a visit in her beachside dreamscape. 

As her life hangs in the balance (literally), a new promo released after Thursday's episode teases that "another person from her past returns."

Meredith, still dressed in a flowy white top and blue jeans, notices a figure -- who's never revealed to the viewer -- up in the distance. "Excuse me!" she yells, trying to sneak a better look at who this mystery person is. Noticeably, she has a smile on her face.

Watch the promo for the next episode, airing in two weeks, below.

Who could this person be? Could it be someone she ended on good terms with? If we were going by the presumed rule that Meredith is having visions of major characters who died on Grey's over the years, that leaves a very small crop of possibilities of who's return would make an emotional and poignant impact on her. 

There's her younger sister, Lexie Grey, who died abruptly following a traumatic plane crash in season 8. Then there's her mother, Ellis Grey, who died in season 3, just as Meredith came back to life from her drowning incident. Or it could be George O'Malley, whose death remains one of Grey's' most unbelievable developments.

If there is no hard-and-fast rule being followed -- and it could be someone who's still living -- could it be Meredith's "person," Cristina Yang? Or would Izzie Stevens make a brief appearance? Or maybe even Addison Montgomery? All we know is we're going to have to wait a little bit longer for the answers.

Kevin McKidd, who directed Thursday's episode, played coy when asked if McDreamy's appearance opened the door for more returns down the line, only saying that Dempsey's return is just the "tip of the iceberg."

"I say nothing. But you know, it's a great premise. What I love about this is that COVID -- many people who have had COVID report that in night time, they get these night visions and strange dreams and [it's] very hard to sleep and it's all lucid dreaming," he told ET. "So this opportunity to do what we're doing with the character of Meredith [through our storytelling] is truly [remarkable]."

"I know nothing," he quipped, pausing for a moment before hinting that he knows more than he's letting on. "Maybe..."

Grey's Anatomy returns Thursday, Dec. 3 at 9 p.m. ET/PT on ABC. For more on McDreamy's return, watch the video below.

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