It helps that regardless of who it happened to, it's a pretty fantastic story. Since part of the film's magic is in the careful way it reveals information, I won't say too much about the details. Basically, we watch as Polley interviews her father, siblings, and a few other key players, all separately from one another, on the subject of, as one sister puts it, "this one thing that happened." Polley and her editor, Mike Munn, cut from one interviewee to another as she asks each of them to tell the story from the beginning. Every participant's immediate reaction to this request is some combination of a deep breath and a statement to the effect of "Oh, boy, from the beginning. This is going to be some serious family soap opera.
Polley's father and mother, Michael and Diane, were Toronto stage actors when they met, in the 1960s. By all accounts Diane was vivacious, extroverted, with a wonderful laugh and a personality that filled the room. Polley's sister recalls watching I Love Lucy reruns as a child and thinking Lucy could be Mom. Dad, on the other hand, though a gifted actor and writer, was quieter, more down to earth. He gave up show business when he and Diane got married in order to provide for the family; Diane felt he'd forsaken his talents.
And that's all you'll get out of me, plot-wise. I don't mean to imply that what happens is particularly salacious or bizarre; it isn't. The reason to be cagey about the details is the same reason the movie works so well. Polley has a storyteller's knack for knowing just the right moment to provide a piece of information to the viewer. For example, at about the 47-minute mark, we learn something about Diane -- something that could have been mentioned at any time -- that adds a new facet to our understanding of her. The same goes for the manner in which other, more critical details are revealed. Without sensationalizing it, Polley tells the story in a way that maximizes its dramatic impact, expertly drawing us into -- and getting us invested in -- the affairs of people we don't even know.
The talking-head interviews are complemented by narration written by Polley's father, read by him in his plummy English actor's voice -- along with footage of Polley, as director, working with her dad in the studio to record this narration. Polley wants to emphasize that Stories We Tell isn't just an account of "this one thing that happened," but an examination of how all families' stories are told. How does learning one truth change your feelings about other truths? How would things be different if this or that piece of information never came to light? We all have our stories, and they are shaped, in part, by how we choose to tell them.