From left, Jeff Bridges, John Goodman and Steve Buscemi in the 1998 film “The Big Lebowski.” (Merrick Morton/Associated Press)

When Adam Welch and Brad Kozlek started a podcast in 2012, they didn’t think anyone was going to tune in. But after a month of making “Gutterballs,” with each episode devoted to a single minute of “The Big Lebowski,” they discovered that one installment had been downloaded 10 times.

“We were just flabbergasted,” Welch said. “Like, who is listening to this?”

To name a few: a man traveling the world who sends the guys photos of himself listening to the podcast atop mountains and in pubs; a Buddhist priest and hip-hop artist who lives in Japan; the founder of the “Lebowski” fan club Dudeism; and Trash Boat, the lead singer of the Polish heavy metal band Godbite, which incorporated “Gutterballs” snippets into its song “Schrödinger’s Scat.”

That’s an eclectic following considering the episodes are marathon length.

“The finale, where we talk about the last 18 seconds of the credits, went for over three hours,” Kozlek admitted dryly. “Like, let’s see how far we can stretch this — and stretch everyone’s patience. But in doing that, something else kind of blossoms.”

One thing that blossomed was the “movie by minute” trend. There are now podcasts that do the same thing with the “Star Wars” franchise and “Goodfellas,” “Clueless” and the DC Cinematic Universe.

Brad Kozlek, co-host of the podcast “Gutterballs.” (Brad Kozlek)

Adam Welch, co-host of the podcast “Gutterballs.” (Evan Holler)

If these movie podcasts sound niche to the extreme, that merely reflects the medium in general. With hundreds of thousands of podcasts out there, some get ultra-specific — sometimes even gimmicky — to tread fresh territory. But movie podcasts reveal how creators are often just digging into their own quirky interests, listenership be damned — viewing their shows, as Kozlek puts it, as “Internet performance art.”

The nichification of podcasts means that blockbusters are extremely rare. For every “Missing Richard Simmons,” which hit No. 1 on iTunes in the United States, there are thousands of guys in basements bloviating about nothing much. That explains why “Serial” remains toward the top of iTunes a year after its most recent episode.

A movie podcast has never taken off in quite the same way, but there are still plenty to choose from. There are shows about films that the hosts have never heard of (“The Blank Slate”) and films that are “so bad that it’s amazing” (Paul Scheer’s long-running “How Did This Get Made?”). “I Was There Too” is a behind-the-scenes look at a movie’s creation, and “The Black List Table Reads” features a promising script that hasn’t yet been bought. Comedian W. Kamau Bell co-hosts “Denzel Washington Is The Greatest Actor Of All Time Period,” discussing one of the actor’s films each episode.

Sometimes the charm is that podcasters don’t seem to care who’s listening. Streaming is like eavesdropping on an in-depth conversation between friends, which has its nostalgic charms: It’s something a lot of people don’t do much since the advent of texting and emails.

Comedian Paul Scheer co-hosts the podcast “How Did This Get Made?” (Courtesy of Paul Scheer)

Listening to “The Projection Booth,” for example, is a little like hanging out with the guys who work at the video store, back when that meant something. Each episode is a deep dive into a movie with a few film fanatics, plus interviews with people who worked in front of and behind the camera. Some of the movies are mainstream — “RoboCop,” “Blade Runner” — but some decidedly are not. Jerry Lewis’s “The Day the Clown Cried” was never even released.

In other words, this isn’t for the casual movie fan. The “Mulholland Drive” episode is three hours long, and you have to wait 90 minutes to hear the reveal from actor Patrick Fischler that much of the footage from the movie was actually shot for a failed television pilot.

Episodes of “The Projection Booth” are a mix of criticism and oral history, and they’re exhaustive. That’s the point. They’re created for posterity, which is why host Mike White doesn’t talk about his own life the way so many other podcasters do.

“The whole reason we try to cut out the personal as much as we can is we try to make [the episodes] timeless so that something will stand up a year from now or six years from now,” he said. “So it doesn’t really matter if I went to see ‘Logan’ two weeks ago. Who cares six years from now? Let’s talk about something we can build upon.”

When he first started the podcast with a friend who goes by Mondo Justin, the pair tried to keep the episodes to 59 minutes. But as time passed, and Mondo moved on, White thought episodes could simply be as long as they need to be. That doesn’t mean they’re unedited. White meticulously excises any “and um”s. They’re also highly planned out. The host estimates he spends about 100 hours working on each installment, including watching the movie and related movies, securing guests, and reading scripts and books. For the episode about Alejandro Jodorowsky’s surreal “The Holy Mountain,” he dug into the movie’s iconography by getting a tarot reading.

That’s a lot of work for about 5,000 listeners a week.

“Some far more, some far less,” he said. “That poor ‘Chicken Park’ episode. . . . Who knew no one would like a discussion of parody films hung on a semi-obscure and majorly clunky Italian film?”

The hosts of “God Awful Movies” also embrace lengthy episodes. The show critiques bad religious films, and their episode on “God’s Not Dead” runs for nearly two hours.

It seems like a podcast that could run out of material, but that hasn’t been a problem 85 weeks in. The trio of Eli Bosnick, Noah Lugeons and Heath Enwright has covered the Christian parkour movie “Leap” and “Vultures of Horror,” which they describe as “a Nigerian Christian demon bird cult classic.” They have a backlog of about 200 titles; meanwhile, the industry keeps churning out more.

A spinoff of “The Scathing Atheist,” the podcast has become even more successful, with each show pulling in about 100,000 listeners, all thanks to social media and word of mouth.

The podcast emerged from Bosnick’s love for bad movies, which is a passion other people clearly share.

“A bad movie so often can just be someone trying their absolute best and finding their limitations as a human being, but only with bad Christian movies do you get really, really poisonous messages,” he said. “When people set out to make a movie about why gay pride parades are a bad idea, you get a magical kind of bad.”

From left, Jesus (Aviv Alush), Mack Phillips (Sam Worthington), Papa (Octavia Spencer) and Sarayu (Sumire Matsubara) in the 2017 film “The Shack.” (Jake Giles Netter/Lionsgate)

They get a lot of feedback from Christian listeners, who tend to have the same message: This may surprise you, but I’m religious and I enjoy the show. That doesn’t shock the hosts. You don’t have to be an atheist to recognize that “The Shack” is terrible.

“I think it’s a welcome distraction for a lot of people,” Lugeons said. “On our other podcast we talk about a lot of topical stuff, and I’m sure you’ve noticed that topical has gotten a lot more depressing recently.”

Maybe that’s why a “small but loyal group” of about 350 continue to tune into “Gutterballs” even after the guys finished “The Big Lebowski” and moved on to more free-form territory. Their recent episodes deal, in part, with the relative hotness of the Skarsgard family of Swedish actors.

Welch thinks Bill — the clown in the upcoming “It” adaptation — is better looking than “Big Little Lies” star Alexander, by the way. Kozlek can’t quite decide. “It depends what mood I’m in,” he said on the show.

Given that the longtime pals live in different places, you have to wonder how much of the show is just an excuse to catch up with an old friend.

“I’d say 97.8 percent of it,” Welch admitted.