Canadian director Sarah Polley (pictured) has opened up about her decision not to do any press around the festival launch of her feature doc debut, Stories We Tell, in a blog post featuring significant plot twist spoilers.

The doc has its world premieres in Venice today, and will have its North American premiere at this year’s Toronto International Film Festival – which kicks off next week – as exclusively revealed by Playback sister publication realscreen in July.

In a blog post for the National Film Board of Canada (NFB), Polley reveals that the film – which has so far been cryptically described as seeing her as “both filmmaker and detective as she investigates the secrets behind a family of storytellers” – actually centers around her own discovery in 2007 that the man she believed to be her father was not her actual biological father.

Following the revelation, Polley strove to keep the news out of press, while both the father who raised her and her newly discovered biological father began writing about the event, leading her to make this documentary.

“What I wanted most was to examine the many versions of this story, how people held onto them, how they agreed and disagreed with each other, and how powerful and necessary creating narrative is for us to make sense of our bewildering lives,” Polley writes in the blog.

“I have decided not to do any interviews about this film until the film is released theatrically and I hope that doesn’t offend, or that journalists who are assigned to cover the film understand this choice after seeing it.

“I desperately want, at least while the film is on the festival circuit, to have people experience and write about the film before the story – or to experience the many stories that this story has become, as opposed to just my version of it. It is, after all, why I made the film in the first place.  It’s oblique, I know.”

Check out the full blog post here.

Polley’s effort is the filmmaker’s first feature-length documentary, following her acclaimed fiction films Away from Her, which won a Genie Award and an Oscar nomination for Best Adapted Screenplay; and Take This Waltz, which played to considerable praise at TIFF last year.

In additional news, the NFB has released the first full-length trailer for the film, which is below:

Stories We Tell (Trailer), National Film Board of Canada