Second only to the late Jim Henson in the annals of the Muppets, Frank Oz has given voice and spirit to such characters as Sesame Street’s Bert, Grover, and Cookie Monster, The Muppet Show’s Miss Piggy and Fozzie Bear, and the Star Wars saga’s Yoda. He has also directed several feature films, among them Little Shop of Horrors and Dirty Rotten Scoundrels. On March 16, he’ll release his first documentary, Muppet Guys Talking, which will be available for streaming exclusively through his purpose-built muppetguystalking.com site.

As its title suggests, this enchanting little film, which runs only 65 minutes, is basically a conversation between five veteran Muppet performers—Oz, Jerry Nelson, Fran Brill,Dave Goelz, and Bill Barretta—about their craft, their lives, and Henson’s benevolent cultivation of them. Most of it was filmed in 2012, not long before Nelson (Sesame Street’s Count von Count, Floyd the bassist on The Muppet Show, and the title character of Emmet Otter’s Jug-Band Christmas) passed away. Oz attributes the movie’s long gestation to his inexperience at assembling a documentary and the fact that “there was no deadline.”

Recently, I met with Oz near his home in New York City—specifically, at a Starbucks adjacent to the site of the old Reeves Teletape Studios, where Sesame Street’s early seasons were produced—to discuss the film. A condensed and edited version of our talk follows.

Vanity Fair: What I like about Muppet Guys Talking is that it reminds me of roundtable discussions I’ve seen by such great comedy troupes as Monty Python and the SCTV gang—except this is a group that most people haven’t seen in discussion before.

Frank Oz: Yeah, that’s us. You can see in the coffee-break part of the film that we’re just the same then as we are on-screen. Part of the reason I wanted to do it was because everyone knew Jim Henson, and some people know me, but nobody knows these guys, and they’re brilliant. The other reason is that my wife, Victoria Labalme, who conceived it, wanted to show people how you can really work in an environment where, as namby-pamby as it sounds, you can do really great work, work like a son of a bitch, and have fun—no politics, no backstabbing, no jealousy. I didn’t realize nobody worked that way. I joined Jim when I was 19, and that was every day. Victoria realized that this was a unique thing.

She had never seen anything like that?

She never grew up with the Muppets.

Did she grow up in Antarctica?

She grew up in a very academic family, but that changed when she met me, ’cause I’m not that academic.

There’s a famous line attributed to the Saturday Night Live writer Michael O’Donoghue, who, in declaring that he didn’t want to write for the Muppets when they were on the show in S.N.L.’s early days, said, “I don’t write for felt.” It seemed to signal contempt for the very art of puppetry.

No, Michael was a curmudgeon, and he reveled in it. He enjoyed that persona. But it wasn’t really about writing for felt. It was writing for anything that he didn’t know how to write for—which he didn’t, understandably. But also, that took away from the other stuff that was happening, because when Saturday Night Live first came on, we were the only ones known. John [Belushi], Danny [Aykroyd],Chevy [Chase]—no one was known. And then, after a few shows, they started getting very successful, and it was obvious that the Not Ready for Prime Time Players were being known more than the Muppets. When that happened, the Muppets were just taking up room when the cast could have done a sketch by themselves.

But I’m wondering if you were motivated to do Muppet Guys Talking by the idea that people don’t understand how much goes into your craft.

Well, yeah, I think that’s part of it. But it’s not a retaliation. It was just because I felt it was time for recognition for those people who really worked hard, and who are brilliant, and who don’t get that recognition. The difference is that we had a man who led us that way. That’s the hard part for people to find.

“Genius” is a such a promiscuously used word. But would you call Jim Henson a genius?

Yeah, I think he’s a genius in the same way that Einstein’s a genius, in that they both played. He had the same sense of play that Einstein had—of using it to instigate ideas. Jim’s play caused him to do genius things.

In the film, you talk about how, in order to do justice to your characters, they have to have a whole elaborate backstory that the audience is not even aware of. Could you thumbnail a few of these for me?

Sure, sure.

Fozzie.

He lived with other bears in the cave, and he was just funny. He was cracking up the bears, but then the bears hibernated, and he wasn’t sleepy. So he decided, “I’m gonna go out and make people laugh.” And it turns out that maybe the bears thought he was funny, but nobody else did.

Piggy.

It’s very elaborate. I mean, she’s a damaged person—

A damaged pig.

Well, you know, I have to take it seriously, because if it was funny, it wouldn’t be funny. I have to be serious, because whatever damage she has in her life, and whatever inconsistencies, whatever insecurities, whatever lack of talent, she desperately does not want to be that person. She came from a farm, and she had to leave home because her father died in a tractor accident. And as her mother was alone and Piggy grew up, it was fine. But then, as she got older, these suitors who came for her mother paid more attention to Piggy, and there was tremendous tension. Finally, Piggy just had to leave and go it alone. She didn’t have anything, really, so, like many single women, she had to take care of herself.

Grover.

Grover is interesting. He is somebody who tries very, very hard to please—to try to do the correct thing to the degree that he doesn’t use contractions. So, in other words, instead of saying, “I couldn’t do this,” he would say, “I—could—not—do—this!” Because by saying “couldn’t,” he’s not trying hard enough. He’s got to be righteous.

Bert.

I had trouble with him as a character in the beginning because there was no character there. While Ernie was cute and cuddly, Bert was just this stick, and I was very frustrated because he was so boring. And then I realized, “That’s what he’ll be. I’ll make him the most boring character in the world!” I took that negative and made it positive. So now his favorite color is gray. He loves oatmeal and white bread. He studies the various tributaries of the world. Absolutely boring shit that nobody cares about, but to him, it’s fascinating.

What about Yoda? Did George Lucas do most of the work on him?

George and Larry Kasdan both wrote the part, but then, I fleshed it out for my own sake.

So what did you bring to Yoda?

George and Larry wrote the backwards language, but it was only used part of the time, so I asked George if I could do that all of the time. What I thought Yoda had was tremendous gravitas. Still does. At the same time, as strong and powerful as he is, he’ll also laugh—not unlike a Zen master, not unlike the Dalai Lama. You’ll find him laughing even when his Tibet is being destroyed, and people being killed, and the libraries burned. There’s the value of the gravitas, and there’s value in levity.

There’s an interesting point in the film when Fran Brill, the sole woman of the group, says she never felt like one of the guys, and you are actually surprised.

Right. I was surprised because she’s our sister. You know, we’re brothers and sisters. But I realized what she was saying: she couldn’t emulate us. That’s different than not being a part of us. She said, very poignantly, “I had to retain my femininity. I couldn’t just try to be a guy. I had to be a woman still.”

She also talks about giving as good as she got. As when, between takes, Cookie Monster looked up Prairie Dawn’s dress—

Lookin’ for cookies. That’s what he does.

Good lord. And Fran says she had Prairie Dawn retort, “Yes, and my underpants say TUESDAY on them.”

Yeah, we screwed around. If you don’t screw around between takes, how do you all of a sudden be funny on the next take? You can’t do that. What we do is screw around in an oddly professional manner. Occasionally, we’ll hit on something, and somebody laughs—I laugh, or she laughs—and it’s “Hey, that’s great. Let’s use that in that piece.”

So would Cookie Monster use off-color language between takes?

No. Muppets would never use off-color language. We would never use profanity. It is too fucking easy. Also, they’re too pure. They would never do that.

So what was the screwing around?

We learned that what was being heard in the control room was also being piped into the offices of the executives over at the Children’s Television Workshop. So we’d talk about the C.T.W. executives: “Do you think anybody’s watching this? No, they’re too lazy.”

You joined Twitter in December, before the release of The Last Jedi. Was that because of people like Rian Johnson and Mark Hamill being so active on it?

No. I love Rian. He’s terrific. But I don’t like social media at all. I’ve been avoiding it for years. Then I was told that maybe it would help Muppet Guys Talking if I got on Twitter. It took me a long time to learn what the hell I was doing.

Not really. You went from 0 to 60. One day you were a novice, then you were tweeting like Joy Reid.

What’s happened is that people have asked me, casually, if I wanted to write a book, and I said no. I’m much too lazy for that. But what I found was just throwing out my feelings on Twitter was the same thing as writing a book, without trying. It was so nice. I just like talking to fans.

I still think you could do a book.

I’m too lazy. I’m too private.

But I have a good title for it.

What?

Deeply Felt.

That’s another reason I’m not doing the book.

CORRECTION (10 A.M.): As first published, this story mis-stated the price of Oz’s documentary. It will not be free.

Get Vanity Fair’s HWD NewsletterSign up for essential industry and award news from Hollywood.David KampDavid Kamp has been a Vanity Fair contributing editor since 1996, profiling such monumental figures of the arts as Johnny Cash, Lucian Freud, Sly Stone, and John Hughes.