Patrick Dempsey discusses his surprise “Grey’s Anatomy” season 17 premiere return during an appearance on Wednesday’s “Ellen DeGeneres Show”.

Dempsey’s character Derek Shepherd, who tragically died five and a half years ago, came back in a beach dream after Meredith (Ellen Pompeo) collapsed in the Grey Sloan Memorial Hospital parking lot.

As DeGeneres quizzes Dempsey on his big return, he says he and Pompeo brainstormed together and thought “how great it would be for the fans to see everyone reunited in this sort of bizarre way.”

“And to the credit of the writers, Krista [Vernoff] came up with this great idea where I will come and visit her in her COVID dream,” Dempsey says.

It hadn’t yet been confirmed whether Meredith did have coronavirus, but she has been working almost exclusively with coronavirus patients so it was a strong possibility.

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Dempsey adds of how many episodes he’ll be in this season, “I’m not sure how many I know I’m throughout this season, he comes back to visit.”

“There are so many souls that we have lost right now so the thought of having angels around us is very comforting, certainly to me,” he adds of his return, before saying of the response: “The impact of the response has been incredibly overwhelming and very moving.”

The actor also talks about his daughter Talula, a college freshman in Washington, and how his twin sons, Darby and Sullivan, are coping with learning from home.

Plus, since Dempsey “treasures” his “Ellen” underwear, the talk show host surprises him with a brand new supply.