Stephen Colbert had a visit from a comedy legend on The Colbert Report last night, and things went completely off-the-rails before they even began.

When Colbert first approaches Cosby, he's staring into the middle distance, seeming completely disinterested in being interviewed. Soon enough, the conversation revs up, turning to Betsy Ross, haunted houses, and open-faced ball sandwiches. All the while, Cosby seems like he's on a different planet, speaking slowly, offering left-turn quips and stream-of-consciousness observations.

It's tempting to wonder what's going on in his head here—is he getting senile or something? or high?—but his wit and sense of timing remain impeccable. As the interview progresses, especially during part two and the extended cut, his manner becomes more lucid and his humor less surreal. It's not the first time Cosby has pulled this kind of thing on late night TV.