Over the past decade, actor/director Sarah Polley has dealt with some pretty major issues in her movies -- the onset of Alzheimer's in "Away From Her" and marital infidelity in "Take This Waltz" -- but now, in her latest directorial venture "Stories We Tell," she's making it personal.

*SPOILER ALERT* -- do NOT read on if you don't want to know!

Set to screen at this year's Toronto Film Festival, "Stories We Tell" isn't fiction. It's her first-ever documentary and it's about families, and how each family member often has different versions of the same story to tell.

But, as Polley wrote in a blog for the National Film Board of Canada, the documentary is actually more of a personal tale. After many years of insider family jokes about her parentage, Polley discovered in 2006 that she was actually the product of her mother Diane's extra-marital affair. In other words, the father she grew up with was not actually her biological father.

According to The Globe and Mail, "Stories We Tell" chronicles some of this revelatory information while simultaneously peppering in staged recreations. At some turns, the documentary is ambiguous, but in other scenes (especially after reading Polley's blog), it's clear that this is mostly an autobiographical project.

Polley states in her blog: "I’m not claiming that my film lacks self involvement but 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. I wanted the story told in the words of everyone I could find who could speak about it. Whatever my own feelings are about the events that are outlined, about the many dynamic and complicated players or the stunning, vibrant woman my mother was, they are ephemeral, constantly out of my grasp, they change as the years pass."

Canadian media outlets were left flummoxed after numerous TIFF press releases about the film stated that Polley would "not be participating in any interviews" for the movie -- a very bizarre thing considering Polley lives and works out of Toronto. This, at least, helps explain why Polley doesn't want to be poked and prodded about very personal issues.

"Stories We Tell" premieres at TIFF on September 7.

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• 'Antiviral'

  Syd March is an employee at a clinic that sells injections of live viruses harvested from sick celebrities to obsessed fans. When he becomes infected with the disease that plagues superstar Hannah Geist, he must unravel the mystery surrounding her before he suffers the same fate.

• 'Stories We Tell'

  Sarah Polley is both filmmaker and detective as she investigates the secrets behind a family of storytellers. She playfully interrogates a cast of characters of varying reliability, eliciting refreshingly candid, yet mostly contradictory, answers to the same questions. She unravels the paradoxes to reveal the essence of family: a messy, intense and loving tangle of contradictions.

• 'Midnight's Children'

  At the stroke of midnight on August 15, 1947, as India proclaims independence from Great Britain, two newborn babies are switched by a nurse in a Bombay hospital. Saleem Sinai, the illegitimate son of a poor Hindu woman, and Shiva, the offspring of wealthy Muslims, are fated to live the destiny meant for each other.

• 'Picture Day'

  Forced to repeat Grade 12, Claire's reputation is sliding from bad-ass to bad joke. At night, she escapes to would-be rock star Jim (aged 33), while at school, she bonds with Henry, a nerdy freshman she used to babysit. Eventually, Claire learns the difference between sex, intimacy and friendship.

• 'Still'

  Based on true events and boasting a veteran cast, Still is a heartfelt story about an 89-year-old New Brunswicker who faces jail time when the government tries to stop him from building a more suitable house for his wife, whose health is beginning to fade.

• 'I Declare War'

  A group of friends play an innocent game of Capture the Flag in the neighbourhood woods. One afternoon, the game takes on a more serious tone and the quest for victory pushes the boundaries of friendship.

• 'Inescapable'

  One afternoon, on a typical day at work, Adib is confronted with devastating news: His eldest daughter, Muna, has gone missing in Damascus. Now Adib, who has not been back in over 30 years, must return to Syria and deal with his secret past in order to find her.

• 'Laurence Anyways'

  In the 1990s, Laurence tells his girlfriend Fred that he wants to become a woman. In spite of the odds -- and in spite of each other -- they confront the prejudices of their friends, ignore the counsel of their families, and brave the phobias of the society they offend.

• 'Rebelle'

  Komona, a 14-year-old girl, tells her unborn child the story of how she became a child soldier. A tale set in Sub-Saharan Africa, Rebelle is also a love story between two young souls caught in a violent yet beautiful and magical world.