McDreamy, is that you?!

Patrick Dempsey made a surprise appearance on Thursday night's new episode of Grey's Anatomy. The beloved character was tragically killed off in Season 11 of the long-running medical drama — but apparently Derek Shepherd isn't gone for good!

Sadly, Meredith Grey — played by Ellen Pompeo — was only imagining Derek's return to Grey Sloan Memorial Hospital as a way to keep her going during a difficult surgery.

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It was great to see Derek again — we wish he was back on the series for good!

Click through the gallery below to see the Grey’s Anatomycast then and now!