Watch David Letterman Return to 'The Late Show' for First Time in 8 Years

David Letterman

Last night's episode of The Late Show with Stephen Colbert featured a very special guest, the show's first host: David Letterman.

Letterman, now 76, took the guest's seat onstage at The Ed Sullivan Theater in New York City on Monday evening, joining his successor, Stephen Colbert, 59, for his first wholesome appearance on the show since he retired in 2015.

The Nov. 20 episode not only caught fans up with what Letterman has been up to since departing the series but also delved into Letterman's favorite moments from his time as the late-night talk show's original host.

Letterman, who filmed over 4,000 episodes for the CBS series, had a hard time choosing his favorite as "they were all damn good."

But ahead of The National's performance, Colbert was able to pry deeper, asking Letterman if there were any particular performances during his tenure on The Late Show that struck a chord with him, noting that he still listens to the recorded productions distributed via Live on Letterman.

"It's very kind of you to cite this [the CDs]," Letterman began. "Because it was one of the great parts of the show and the people who booked these acts were great producers and in touch with a wide variety of music and it was a tremendous gift."

"When you don't have that in your life every night, you really, really miss it ...but I was thinking about this," he went on, "Green Day, whenever Green Day would be on I was frightened by the drummer [Tré Cool]. Because whenever they would finish, he would charge the desk and lunge at me–to the point where I assumed he was kidding around or perhaps he actually wanted to hurt me."

"Looking back at that now," Letterman said, "I just think, 'Wow, what a great experience that was.'"

While Letterman clearly misses parts of his old gig, he's happy to see it's continued in such good hands with Colbert, even calling the show a "great success."

"It's not easy, but you make it look so easy," Letterman shared at the top of Monday's episode.

As for Letterman's life now, it's certainly slowed down since he was running the program, noting that as an empty nester he "spends a lot of time Googling symptoms."

"When Harry [Letterman and wife Regina Lasko's son] left a year ago–he's a sophomore [in college] now–we decided we would do one of two things," Letterman explained. "My wife and I had a consult about this."

"One, we would either have another child or get a divorce," he continued, joking, "The paperwork, honestly, is about the same either way, so we're kind of stuck."

When Colbert asked if the couple has spent their time traveling, Letterman shrugged it off with a quick "yeah" before diving into what he's really filled his life with.

"I used to think it was the world, but now I think it's me. I went into a CVS," he shared, "I spent a lot of time Googling symptoms."

"So I go into CVS to pick up the salve," he laughed while explaining the process of checking out at the pharmacy. "The pharmacist [who is helping out a different customer] disappears and comes back with a rod, a yellow plastic rod."

"The guy thanks him and leaves, and now I go up to the desk and all I can think about is [the giant yellow rod]. So I said to the guy, 'I know it's none of my business, but the guy handed you a prescription and you give them a plastic rod,' and he said, 'Yeah.'"

"And I said, can you tell me what the issue is there, and he says, 'Yeah, yeah, going to the bathroom.'"

"And [the pharmacist], says, 'Yeah, yeah, that's where we keep the key to the men's room,'" Letterman concluded as the audience roared with laughter.

He's still got it!

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