On Monday, the actor, 54, shared a selfie on Instagram of him wearing a mask and in the caption evoked one of his popular lines from the show to make a point.
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“It’s a Beautiful Day to Save Lives,” Dempsey wrote along with the hashtags #WearAMask, #COVID19 and #YourActionsSaveLives.
“Grey’s Anatomy” fans will no doubt remember that line as a bit of a catchphrase for Dr. Derek Shepherd, Dempsey's character on the long-running ABC medical drama, that he'd repeat before performing a surgery. Dempsey had played Derek, aka McDreamy, on "Grey's" since its premiere in 2005 until his character was killed off in series' 11th season in 2015.
The actor has previously used the show to remind people of how to help stop the spread of the coronavirus. In April, he appeared in a photo with former "Grey's" co-star Eric Dane showing the proper way to practice social distancing.
“Blurry pic of how to hang out 6 feet apart,” Dane captioned the picture of him in the foreground, with an out-of-focus Dempsey standing behind him standing on a grassy hill.