Netflix Asks: Who is Martin Mull? Union's Zach Kashkett Helps Find the Answer

Musician. Comedian. Actor. Painter. Martin Mull spent a lifetime resisting easy categorization. For Netflix’s new documentary WHO IS MARTIN MULL?, Union Editorial’s Zach Kashkett joined director Neil Berkeley to help answer the question in the title without reducing Mull to any one part of his remarkable life.

The film itself has an unusual history. Bob Saget began the project in 2018, co-directing and documenting his longtime friend before Saget’s death in 2022. Director Neil Berkeley subsequently took up the film, carrying Saget’s original work forward and completing the documentary.

Union came aboard during a natural transition in the editorial process, as editor Jason Zeldes moved on to another project and the filmmakers prepared to complete their remaining interviews. With a wealth of material already in hand, the task became finding the structure, rhythm and balance that could make the film as propulsive and entertaining as its subject while honoring the full scope of Mull’s legacy.

For Kashkett, that meant finding the connective tissue between a career encompassing comedy, music, television and visual art, while leaving room for the more intimate and emotional dimensions of Mull’s story.

“Balancing the comedy, art, and more emotional aspects of Martin’s life was the biggest challenge,” says Kashkett. “Structurally and in terms of pacing, it was a real puzzle to solve. Because Martin was such a prolific artist, choosing which paintings and comedy projects to focus on was also difficult.”

Kashkett spent countless hours working alongside Berkeley and team, testing ideas and reshaping the film as its final form emerged. The collaboration was especially meaningful for Kashkett, who had long admired Berkeley’s work.

“I loved collaborating with Neil and (producer) Sean (Bradley),” he says. “I’ve been a huge fan of Neil’s film Beauty Is Embarrassing for years and had wanted to work with him for a long time. He really trusted me to work through plenty of failed ideas to figure out where the film should land, and I was incredibly grateful for that trust.”

That willingness to explore proved essential to a film about a man whose creative life rarely followed an obvious path. Anchored by archival one-on-one conversations with Mull himself, the documentary draws upon the perspectives of friends, collaborators and comedy figures including Steve Martin, Tom Waits, David Alan Grier, Patton Oswalt, Fred Willard, Norman Lear, Paul Feig, Penn Jillette, Kerri Kenney, Andrea Savage and Ted Sarandos.

Before picture lock with Netflix, the filmmakers screened the film in its entirety for Mull’s wife and daughter, an emotional experience for everyone involved.

Union Co-Executive Producers James Haygood and Katherine LeBlond provided creative input as the cuts developed, while Union’s post-production team carried the film through online, finishing and final delivery to Netflix. Berkeley advocated for a first-time additional editing credit for Union assistant editor Roman Petrov for his additional efforts on the project. 

WHO IS MARTIN MULL? continues Kashkett’s work in feature documentary storytelling. His previous release, Netflix’s Miracle: The Boys of ’80, chronicled the underdog U.S. Olympic hockey team. He has also recently completed a feature documentary about the iconic public-access program The Chris Gethard Show, currently aiming for a festival premiere in early 2027.