A 13-minute documentary about the man behind one of San Rafael's longest-running small businesses will screen steps from his shop next week.

"The Right Fit," directed by Oakland-based filmmakers Nicolas Collins and Max Mollring, profiles Tom Diettrich, owner of Jeans to a T on Second Street. Diettrich, a Chicago native, has run the one-man denim shop six days a week for 49 years, hemming pants in a workshop in the middle of the store and fielding phone calls from customers around the world, according to a profile first reported by the Marin Independent Journal.

The film makes its Bay Area premiere at the Mill Valley Film Festival (MVFF) as part of the "Stay Free" shorts program. It screens at 8 p.m. Monday, Oct. 5, at the Lark Theater in Larkspur and at 2:15 p.m. Tuesday, Oct. 6, at the Smith Rafael Film Center, 1118 Fourth St. Tickets are $13.75 per showing and available at the MVFF film page.

Collins, a Marin native and Drake High School graduate, described the store as an unassuming place behind a blue awning.

"You go inside and then all of a sudden you're transported into this Western-style saloon, where it's floor-to-ceiling jeans and all sorts of Levi's, Wrangler and Lee advertisements throughout the years," Collins told the Marin Independent Journal.

Collins and Mollring spent two years returning to the shop to film Diettrich at work. They captured what the Marin IJ calls his "jean whisperer" talent: remembering past customers' pant sizes. Mollring recalled watching Diettrich help a customer identify a tagless pair of pants. A Levi's historian who visited the shop was stunned by Diettrich's stock and knowledge, according to the report.

Mollring said the project grew from a casual conversation. Collins had told him about the shop. Mollring saw a documentary waiting to happen. He called Diettrich an expert whose loyal customers already knew him as "the guy to go to."

The film is the first co-directed project for Collins and Mollring, who have been friends since 2017. Producer and cinematographer Jonathan Salazar, whom Mollring met at San Francisco State University, rounds out the crew. All three filmmakers and Diettrich plan to attend both screenings.

Collins, who previously screened his 2023 short documentary "Swimming the Rock" at MVFF, said the film is really a story about community gathering places that are disappearing.

The 49th Mill Valley Film Festival runs through Sunday, Oct. 11, with screenings across Marin County.