I feel a little guilty saying this, given the subject matter of the film, but the post-show chat I hosted after a screening of “Act of Killing” at Sundance Cinemas a couple of weeks ago was a lot of fun.

The movie itself, which delves into the psyche of government-sanctioned Indonesian mass murderers, is no fun. But it is brilliant and thought-provoking, and it made me so happy to see by far the largest turnout for a Sundance chat come out — we filled the Overflow Bar, and it was a great conversation, as people shared their reactions to the film, including a few people who lived in Indonesia.

But the next movie I’m doing a post-show discussion for, “Stories We Tell,” deals with somewhat lighter subject matter. The chat will take place after the 6:55 p.m. screening on Tuesday, Sept. 10 in the Overflow Bar, located on the first floor of the theater, right across from the box office. Everybody’s welcome.

Actress and filmmaker Sarah Polley (“Away From Her,” “Take This Waltz”) turns the camera back on her own family in “Stories We Tell,” interviewing family members and friends to discover the story of her late mother, a story that brings with it some truly surprising revelations. It’s a film about the fractured state of a family’s history, how everyone holds their own perspective on past events, knitting fact, rumor and opinion together into a narrative that suits them best. I think it’s one of the best films of the year.

It’s a film that will give us lots to talk about. I hope you can join me!