For the first time in 13 years, Conan O’Brien paid a visit to David Letterman’s TV talk show.

O’Brien took over NBC’s Late Night show from Letterman when the latter bolted to CBS for an 11:35 p.m. slot, all because NBC chose Jay Leno over Letterman. Now O’Brien knows that feeling, too, having left the Peacock Network for TBS all because NBC chose Leno over him. Wonder what they’ll talk about tonight? Of course, you don’t wonder. You know. They know. We all know. Roll the teaser clip!

Letterman presses on:

And then this:

If this situation is even more of a case of history repeating itself, enjoy this clip from August 1991, shortly after NBC picked Leno over Letterman, and Dave swung by The Tonight Show with Johnny Carson. Roll it.