Nick August-Perna co-directed "The Swell Season."

The Swell Season — folk-band buddies Glen Hansard and Marketa Irglova — charmed audiences in 2008, when its ballad “Falling Slowly” from the indie film “Once” won an Oscar. In the movie, Hansard and Irglova played Dubliners who make beautiful music together. In real life, the two fell in love as they made that music — and then they broke up. A new documentary on the duo, “The Swell Season” (co-directed by Nick August-Perna, Carlo Mirabella-Davis and Chris Dapkins), tags along on two years of Hansard and Irglova’s post-Oscar world tour. August-Perna spoke to Express about the film.

What impact did “Once” have on your documentary?
It created this parallel life for Glen and Marketa. I think a lot of people saw “Once” as a documentary. But we were really interested in this couple that was under the scrutiny both of the world and of us.

How did Glen and Marketa react to your filming their relationship?
They were quite hesitant to have the romance be the subject of the documentary, and it took some convincing. They were very much in love when we embarked on the tour.

How would you characterize their connection with their fans?
Theirs is a different relationship to fans than most. I always think about how fans would never go up to Bob Dylan and say, “Can I give you a hug?” People feel very comfortable with Glen and Marketa. They’re very open and bare onstage.

Lately, they’ve been touring separately. Does that surprise you?
There was always the idea that this might happen. And, of course, there’s this double meaning to the idea of “The Swell Season,” which is the name of their band but also a name for a special time period they went through together. We all felt that it was an ephemeral, intense, fleeting part of their lives.

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