Matt Wolf’s latest project started with a casual joke. The director of “Teenage” and “Wild Combination: A Portrait of Arthur Russell” had been comparing notes with his friend Ericka Naegle, with whom he was working on a short profile about “Eloise” creator Hilary Knight, when she brought up having to cold-call Steven Spielberg about something to which he replied, “I had to cold-call the owner of a clothing-optional bed and breakfast who was adopted by his older lover today.”

While Wolf wasn’t exaggerating – he had become fascinated with generations of gay men and women who cleverly facilitated adoptions of one another to obtain the legal protections that they would have if they had been allowed to marry – Naegle had a serious surprise for him, mentioning that her uncle Walter had been adopted by his partner.

“I go home later that night and I Google her uncle’s name and immediately I realized that his partner had been Bayard Rustin,” recalls Wolf. “I knew who Bayard was and really revere him as a seminal political figure from the civil rights movement and also as a gay person, so at that moment, I’m like, ‘Wow, that’s an amazing story.’”

The filmmaker does justice to the remarkable romance and then some in “Bayard and Me,” which tells of the unconventional arrangement forged by Rustin, a civil rights leader on a number of fronts, mentoring the likes of a young Martin Luther King, Jr., among others, and Naegle, taking advantage of the 37-year age gap between them to ensure they’d have such rights as hospital visitation for family members. But the 16-minute short, which premiered earlier this year at Sundance, goes further, using Rustin and Naegle’s shrewd workaround as an entry point to a broader consideration of how the fight for gay marriage has correlated with a larger place for the community in the mainstream. Wolf, who specializes in creating collisions of archival material that can tell so much in a single splice about how the past continues to inform the present, combines a visit today with Walter at his quiet flat in New York with a flood of footage of wilder days of passionate protests that enabled such an existence.

In the coming weeks, “Bayard and Me” is making its big-screen debut on both coasts, presented at Outfest in Los Angeles on July 9th and as part of a program curated by Wolf himself at the Metrograph in New York on July 21st, and before the screenings, he spoke of the curiosity that led to the compelling doc, as well as how he went about gathering footage for the film and what inspirations for the film he’ll be showing as part of the Metrograph screening.

How did this come about?

Storycorps, the oral history radio project, had asked me to help them find some interesting stories because they were doing a queer history initiative and I had heard of this phenomenon called intergenerational gay adoption. It’s not a well-known history and there’s not even a language to discuss it in a way. The first time I heard about it was in a Vanity Fair story about an architect named John Woolf, who had pioneered the “Hollywood Regency” style of architecture. But I’m really drawn towards hidden histories, particularly about gay culture. Today, gay marriage is so much part of the mainstream and it’s interesting to look back at a time which people sought those rights in more subversive or underground ways.

So this first existed as a radio project. We went into the StoryCorps booth by City Hall and Walter’s niece, my friend Ericka [Naegle], interviewed him for three hours and that interview is part of StoryCorps’ oral history collection at the Library of Congress. Then a producer and myself turned it into a short radio piece, but I knew I wanted to go deeper because it was a two- or three- minute piece and it was a story that deserved a longer form. So about a year later, I was saying to Walter, “I’d love to make this into a film.” I just started going to his house and scanning photos and I found a partner in Super Deluxe, who wanted to make it a film as well.

There’s such great footage of Bayard Rustin in the film. Did you know what was out there or was it hard to come by?

Because of the 2003 documentary “Brother Outsider,” I knew that there was good footage of Bayard. There’s some great footage of him debating Malcolm X, but [in general] just lots of footage of him because he was a fairly visible public figure, even though he’s not that well-known. But what I really wanted to do was not just make a biography of Bayard, but really telescope into the story of his relationship with Walter and to show this line of continuity between the civil rights movement and the gay rights movement.

That’s a feeling you achieve with simply the clips you use – for instance, using clips from the 1950s to illustrate the adoption process that in Bayard and Walter’s case took place in the 1980s. How did you want to toy with chronology in that way?

In all of my films, I like to blur the past and the present. That’s why I shot photos and portraiture of Walter in 16mm really to make this transition between the past and the present really seamless because I think there’s a lot of contemporary resonance in this story. In terms of using 1950s adoption footage, a lot of that was just playing with the archetypes of your conventional nuclear family and what Bayard and Walter really were doing was reimagining those archetypes and the cliches of what families look like.

Besides the Outfest screening in Los Angeles, there’s a special event that you curated at the Metrograph in New York built around the inspirations for the film. How did that come about?

I’m excited about that. The Metrograph is my favorite movie theater. I screened my film “Wild Combination” there and moderated some Q & As, so it’s kind of a home for me, and it’s great to be able to bring this film and a program of other shorts that I’ve organized to compliment this film as well. Some of it is stuff that I found along the way that I couldn’t use in [“Bayard and Me”], like the amazing debate between Malcolm X and Bayard Rustin that was on NBC back in 1962, and then I found out about Harold T. O’Neal through the GLBT Historical Society. They have an incredible film archive and [O’Neal] is this amateur filmmaker who pretty obsessively started documenting his life as a gay man in the 1940s and he had actually adopted his younger boyfriend who appears in many of his films. From the 1940s and 1950s, we have almost no imagery of what gay life looked like at that point because it was totally underground, so these films are just remarkable, and I’m showing one of those home movies and mashing it up with some early gay liberation music, just to do a remix of before and after gay liberation.

The wonderful documentary filmmaker Arthur Dong recommended this documentary from the ‘90s called “Chicks in White Satin,” which was nominated for an Oscar. It’s two Jewish lesbians preparing for their wedding, and what I love about the film is the ‘90s styling of everything, but also just how awkward the whole thing is. They wear these poofy white dresses and have a registry at Macy’s — they were really sticking to all the traditions and it’s at a time before people were doing it, so It’s just campy and funny. Then the final film in the program is one of my favorite shorts of all time called “Marta: Portrait of a Teen Activist,” a parody of an ACT UP activist who’s an overzealous teenager. I was an overzealous teen activist, so I really relate. [laughs] But I think part of what was so great about ACT UP besides their rage was their sense of humor and the way that they ingeniously created dramatic visual interpretations of their movement. This is an amazing example of humor coming into it as well and it’s great.

What’s it been like bringing out “Bayard and Me” out into the world in general?

I’ve been getting great feedback. It’s been playing festivals and I haven’t been able to be there in person because I’ve been in production on a lot of stuff, but at Sundance where the film premiered, it was great to hear people come up afterwards and to talk about their connections to Bayard or realizing that one guy went to the same high school as Bayard and his high school is named after Bayard but he never knew the history of him. We did a screening for teenagers where they wrote reflections on post-it notes after the screening. It’s gratifying to see how inspired they were by this person from history who very few people had heard of who was so significant and [how] people continue to discover Bayard and the influential work that he did.

“Bayard and Me” will play at Outfest in Los Angeles as part of the Silver Shorts program on July 9th at 7:15 pm at the DGA, and at the Metrograph in New York on July 21st at 7 pm.