Zach Galifianakis regrets asking Obama this 'Between Two Ferns' question

"Between Two Ferns: The Movie" on Netflix (streaming now) presents a star-studded probable finale to the viral internet reign of the absurdist Funny or Die show of the same name, sending host Zach Galifianakis and his parody public-access series on a road trip.

But before the series, which began more than 10 years and 20 episodes ago, takes its signature plants out of the spotlight, we asked for some dirt.

Galifianakis and the film's director, Scott Aukerman, took USA TODAY behind the ferns for some insider tidbits about the series, from jokes that barely survived, stars that almost were on the show and a back story on the show's problematic theme song.

Zach Galifianakis almost dropped his most memorable jokes because they were ‘too much’

Though Galifianakis plays a contemptuous interviewer unafraid to ask celebrities inappropriate questions in “Ferns,” in real life the comedian refused certain jokes. That is, until Aukerman convinced him otherwise.

For example, Galifianakis balked at asking Natalie Portman: “You shaved your head in 'V for Vendetta,' did you also shave your V for vagina?”

“I thought that that question was too much. I actually asked them to edit that out,” Galifianakis says.

After that interview, the “Ferns” co-creators developed a “good cop/bad cop” dynamic, as Aukerman puts it. “He reads the paper and goes, ‘Oh, I'm not going to say this,’ and then looks to me," and Aukerman will adamantly insist Galifianakis ask the question.

This happened in 2014 when he interviewed Barack Obama and asked, “How does it feel to be the last black president?”

Some guests, including Hillary Clinton, worry how they'll come off

“Ferns” rules require guests to come on the show without knowing the questions beforehand. When the camera rolls, Galifianakis improvises and riffs on prewritten questions. Celebrities just have to react.

Ahead of the 2016 presidential election, Hillary Clinton’s camp wanted the nominee to do a “Ferns” interview, but “they didn't want to do it the way that we normally do,” with Clinton going into the interview blind. Aukerman refused and Clinton ultimately agreed to his terms.

But her team was scared about how it would turn out.

“People get really worried about (the interview), and then you put it out and they love it," Auckerman said.

Bernie Sanders passed on an interview; Oprah and Elton John pulled out last minute

“We asked Bernie Sanders to do one and he said no,” says Galifianakis, who appreciated that the politician wouldn't try to win over voters with an off-brand comedy video. “I respected him so much for that.”

Less than appreciated: When representatives ask to get their celebrity client on the show, and the star ultimately passes after planning has begun. According to Aukerman, that happened with Oprah Winfrey and Elton John.

While shooting
While shooting

'Ferns' creators don’t take notes from stars, with a couple of exceptions

The Obama jokes had to be cleared by his speechwriters beforehand.

“That's the one that we sort of struck a compromise," says Aukerman, who understood that an exception could be made for the commander in chief.

And when it came to the 2011 Jennifer Aniston interview, Galifianakis ultimately felt bad about the plan to surprise her with a Brad Pitt lookalike on camera. He asked her beforehand if she was OK with it, and, as Aukerman recalls, “She, I think rightly, was like, ‘It's not that I don't think it's funny. It's just anything that continues this conversation about me and Brad Pitt just prolongs me having to talk about it.’ And so we said no.”

The theme song became a thorny issue

Fun fact: The “Between Two Ferns” theme is actually taken from a certain famous 1976 Robert De Niro movie. Aukerman didn't know that 11 years ago, when the music became part of the first “Ferns” episode.

“I thought it was elevator music,” says Aukerman. “It was a low-budget show and we couldn't write music for it." He had no idea the music was from “Taxi Driver” and would ultimately cost so much money to use. “It's literally been a problem for 10 years."

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This article originally appeared on USA TODAY: 'Between Two Ferns': All the best celebrity dirt, from Obama to Oprah