After 22 seasons, 4,262 episodes and tens of thousands of celebrity guests, it's no surprise David Letterman's departure from the Late Show is hitting a lot of stars pretty hard.
Actors, comics and musicians have been taking to Twitter, Instagram and Facebook to share their congratulations and memories from their time on Letterman's show.
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Some even shared stories of how the 68-year-old TV personality influenced their lives and careers. For example, Parks and Recreation star Adam Scott tweeted: "A good 80% of why I wanted to do any of this was to one day sit on Letterman's couch."
Some stars didn't want to accept the reality of the situation. Jennifer Lawrence posted a photo begging Letterman not to leave.
Even his fellow late-night hosts encouraged their viewers not to miss his last episode.
Many celebrities just wanted to make it known that they appreciated all the laughs and good times from Letterman's long, groundbreaking career in late-night television.
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This truly is the end of an era, and it will be interesting to see how his successor, Stephen Colbert, does behind the Late Show desk.
In celebration of his long and beloved career, check out Dave's 10 best Late Show moments.