Conan O'Brien had a highly unusual message for viewers midway through his show on Wednesday night: Change the channel.
The late-night host asked viewers to record his show on TBS, but switch to CBS to see David Letterman's final "Late Show" as it aired.
"Conan" starts at 11 p.m. while "Late Show" starts at 11:35 p.m., and O'Brien used part of the first 35 minutes of his program to pay tribute to his long-time mentor, recalling the time he took over "Late Night," the show Letterman started at NBC.
"Way back in 1993, I took over David Letterman's iconic late-night television show. I was a complete unknown with absolutely no experience performing on television," O'Brien said. "I was utterly and totally unprepared for that enormous job."
At first, the show tanked.
"I got the shit kicked out me," he admitted. "Critics despised me, the ratings were bad, my skin broke out."
O'Brien said everybody thought the show would be cancelled.
"And then something miraculous happened: After four really dreary months, out of the blue, we got a message at the show that David Letterman wanted to come on the program as a guest," O'Brien said. "Dave wasn't just the biggest star on late-night at the time, he was the biggest thing on television. He didn't go on other people's shows. It was like the Beatles asking Maury Povich if they could stop by and sing a couple of tunes. It was that absurd."
O'Brien thought the offer was a prank. But it wasn't -- Letterman arrived and "blew the doors off the place."
The rest is history.
The show recovered and O'Brien would have the time slot until his ill-fated takeover of the "The Tonight Show" in 2009.
Check out O'Brien's tribute to Letterman in the clip above. And watch below as he and guest Patton Oswalt note the time at 11:35 p.m. and urge viewers to change the channel.