Patrick Dempsey Says Fan Reaction to His Grey's Anatomy Return Has Been 'Overwhelming'

Patrick Dempsey is reflecting on the fan response to his surprise Grey's Anatomy return.

While appearing virtually on Wednesday's episode of The Ellen DeGeneres Show, the 54-year-old actor opened up about his recent appearance on the ever-popular ABC medical drama five years after his character, Derek Shepherd, was killed off.

Dempsey told host DeGeneres, "The response has been incredibly overwhelming and very moving."

The actor explained that he and longtime costar Ellen Pompeo got together earlier this year and questioned how they could get people to wear masks and make an impact amid the ongoing coronavirus pandemic. The idea of him returning to Grey's Anatomy for the seventeenth season was then born.

"What a great opportunity for people and how great it would be for the fans, really, to see everybody reunited in this sort of bizarre way," he said.

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During last week's Grey's Anatomy season premiere, Pompeo's Meredith Grey collapsed in the hospital parking lot before the show cut away to a dream sequence that featured her reuniting with Dempsey's character on a picturesque beach.

Crediting the show's writers and showrunner Krista Vernoff with making his return happen, Dempsey told DeGeneres, 62, that it was a very tough secret to keep.

"Nobody knew about it other than ABC of course, some people at ABC, Krista [Vernoff] and then Ellen [Pompeo] and myself. And that was it," he revealed. "And then we started talking to the directors, which would be Debbie Allen — who's amazing — and Kevin McKidd, who's one of the directors that I worked with. And that was it."

"No one knew until I showed up on set that day," Dempsey added. "And then we were really concerned that someone would take a picture and it would be out somehow, but we managed to keep it a secret, which was pretty phenomenal."

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Speaking with Deadline after last Thursday night's episode of Grey's Anatomy, Dempsey told the outlet that it was "really enjoyable" to get back into character.

"It was really exciting and fun, and it was great to see everybody. ...," he said. "The dynamic behind the camera had changed. There’s much more diversity within the crew. There was a nice balance, too, of equality that I was seeing. So, culturally, there was a lot of things that were different, that I thought were very positive and very inspiring, actually."

Pompeo, 51, and Dempsey shot the scene together after being tested for the coronavirus. The lead actress said it "felt great" to reunite with her former costar.

"Patrick and I have this chemistry where I think even from when we first met, for some reason it just felt like we’ve known each other for a hundred years, and it’s just the same feeling," Pompeo told Deadline. "It’s like riding a bike, we just have a chemistry and a dynamic that’s always served us well, and I think we have a genuine affection for each other."

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Also during his visit to The Ellen DeGeneres Show, Dempsey discussed how often fans can expect to see Derek throughout the rest of the season.

"I'm not sure how many [episodes I am in]," Dempsey shared. "I know I'm throughout the season. [Derek] comes back to visit."

Vernoff, 46, similarly told the Los Angeles Times last week that Dempsey's character will appear more.

"We will see more of [Derek] this season," she told the outlet. "This was not just a cameo. He will appear three more times."

Grey's Anatomy airs Thursdays at 9 p.m. EST on ABC.