The new Grey's Anatomy season has been full of surprises. "Meredith" (Ellen Pompeo) has contracted COVID-19 and is battling the disease. Meanwhile, her late husband "Derek" (Patrick Dempsey) has reappeared in dream sequences. But now, we can add another character to the list of comebacks.

Grey's Anatomy season 17: New comeback in episode 4

In the new Grey's episode, shown on Thursday night, there was another shocking reunion. A trailer had previously teased a return, but the identity of the guest remained a secret until the end.

Then came the surprise: It was none other than "George O'Malley" (T.R. Knight) returning to the series.

T.R. Knight ("George O'Malley") returns to Grey's Anatomy

In the episode, "Meredith" was still in critical condition and "George" reappeared in a dream just as "Derek" had earlier. The two friends talked about death, grief, and the influence "George" had on "Meredith."

"You changed my life, 'George.' I know didn't say it then, but it's true," she told her former colleague. Actor T.R. Knight had left the series at the end of season 5, after his character died tragically in a bus accident. Fans once again raved about the reunion they never imagined was possible.

At the end of the episode, "Meredith" was still in bad shape. And "Tom Koracick" (Greg Germann) also fell ill with COVID-19. At first he had only mild symptoms, but his condition got worse.

U.S. viewers can expect to see new episodes for the next two Thursdays on ABC. A premiere date for worldwide viewers remains undetermined for now. For more, see actress Camilla Luddington talk the new direction for "Jo" in season 17 here.

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