When I sat down with Mark Duplass and Lynn Shelton to discuss their film "Your Sister's Sister" at Sundance this year, I was well aware of just how tight time was for everyone.  I was working to juggle interviews and screenings, and Duplass was there representing two movies of his own and supporting his wife, Katie Aselton, who was there with her film "Black Rock."  He was so stretched thin that I saw him napping in a chair between interviews.

Even so, once we all sat down together, our allotted interview time ended up stretching a bit because the conversation was going well.  I've gotten to know Mark and his brother Jay on a professional basis over the last few years, and I think it's been a genuine pleasure watching them develop their voice from film to film, expanding their audience while maintaining their own sensibilities.

I saw Shelton's "Humpday" at Sundance a few years ago, and I admired the way it navigated a potentially gross joke to create something smart and heartfelt and funny.  I was excited for "Your Sister's Sister," but unprepared for what a jump Shelton seemed to make from one film to the next.

It's always interesting when an actor is also a filmmaker, but is willing to hand himself over to another filmmaker and relinquish control.  Duplass has been doing more and more of that, and I think the result is that he seems to be getting better at both jobs because of these other experiences.

This was one of those chats that stopped feeling like a formal interview and started feeling more like a real conversation, something that doesn't always happen under circumstances like this.  I wish more people were able to speak about their work with the same sort of casual, unforced pleasure that both Duplass and Shelton seem to take in this new film.

"Your Sister's Sister" opens tomorrow.