Zach Galifianakis Upset Jennifer Aniston With a Brad Pitt Lookalike Joke

Zach Galifianakis has opened up about the moment he went too far on Between Two Ferns when Jennifer Aniston was his guest.

Aniston was a guest on The Hangover star's comedy show, but moments before they went to air, he revealed to her that he had a hired Brad Pitt lookalike who was waiting backstage.

Between Two Ferns with Zach Galifianakis is the comedian's popular web series turned Netflix movie where he sits down with A-list celebrities, often leading to awkward and insulting interactions.

Galifianakis was discussing his show and some memorable backstage moments from it on David Spade and Dana Carvey's Fly on the Wall podcast. As well as the tense Aniston moment, he also revealed how he thought Sean Penn wanted to "deck" him after an episode, and a hilarious post-show note Natalie Portman sent him.

"I don't know if I've even I don't know if I've spoken about it," Galifianakis started after being asked about a show where things had gone "sideways."

"I interviewed Jennifer Aniston, you know from SmartWater?" he began, referencing his 2011 episode with the Friends star. "And in the wings I had a Brad Pitt lookalike. I wanted to tell her about it before we started filming. So I kind of asked her if I could have a word with her, you know, like a vice principal."

Galifianakis continued, "And I said 'I have a Brad Pitt lookalike here.' And as soon as I said, I read her face. And it was her—I felt so bad.

"I don't even know anything about that thing [their relationship]. I know that was in the papers but I don't know much about it. But so, of course I called it off."

Pitt and Aniston broke up in 2005, with the Between Two Ferns episode airing almost six years after their divorce. The former married couple have since become friends, being spotted at awards ceremonies talking to each other. Pitt later appeared on Between Two Ferns with Zach Galifianakis in 2014.

Galifianakis spoke at length about the show and how his celebrity guests are usually in on the joke. However, he thinks Sean Penn was furious with him by the time they wrapped.

"I would like to one day talk to him about the one we did. It was an interesting day," Galifianakis said of Penn's 2010 episode.

"He's a good actor. I think he may have been ready to deck me in real life. I don't know. Maybe he was doing a method thing?

Galifianakis continued, "I have worked with him, not that I know him but he has a good sense of humor, is really funny. Huge laughter, and he loves to go see stand up. But in that moment it was odd."

SNL alumnus Spade weighed in, recalling watching that episode. "Sean is very funny, unlike his persona out there. So I liked that he was going along with it, and he was so serious, and goes 'I could walk over there and knock you the f*** out right now.' And even I was like 'goddamn he gave that a good reading.'"

"I don't think he was offended," Carvey said.

"I'd like to ask him. We haven't spoken since," Galifianakis finished.

Galifianakis was speaking on the latest episode of the Fly on the Wall podcast where Carvey and Spade speak to guests about their experiences hosting, writing for, or being a cast member on Saturday Night Live.