Always give a director a second chance. And a third. And a fourth. Maybe not five, but, you know, plenty of them. Canadian Sarah Polley's Stories We Tell is a great example why. I could hardly stand Polley's last film, the dramatic snooze Take This Waltz, and when I first read about her newest one -- a documentary about her family of all things -- I may have rolled my eyes and let out a heaving sigh. One lousy work doesn't mean an artist has nothing interesting to say, of course, and this film is effective on two levels.

Using a blend of home videos, in-depth personal interviews and loose artistic reenactments by her and her family members, it recounts Polley's discovery, decades after her mother's death, that she was the product of a prolonged affair between her mother and another man. It is, at different turns, humorous, painfully honest and deeply sadenning. It is also consistently and uncomfortably captivating. An ordinary family's deepest, darkest secrets are laid bare -- all of its members pressed in to duty, some of them seemingly more willing than others.

You can't help but take voyeuristic pleasure in the juicy secrets that Polley has decided to share with the world, even if you feel mostly guilty about that fact. But her openness about it all is just a sliver of the appeal.

The identity of her biological father is unwrapped like a mystery. It starts with the family jokes that Sarah had a different father. It follows her mother, Diane, to Montreal in the 1970s, where she was separated from her husband Michael for a few months -- the man long assumed to be Polley's biological father -- and where she acted in a play and engaged in the affair that produced her youngest daughter. Then it bounces back to the marital troubles between Michael and Diane, then back further to Diane's shattered first marriage, then forward to her untimely death from cancer.

This is a good story. It has a lot to say about love, marriage and infidelity. It also has a lot to say about stories themselves -- the way memories are passed from one generation to the next, inevitably corrupted when the person who is passing them on leaves them to someone who can not help but color them with their own perspective.

Polley draws upon her own riveting personal history in Stories We Tell, but what makes her documentary so good is that it manages to be quite a bit more than the type of family gossip that you can find on a daytime soap opera.

Good directors have the instincts to know a compelling story when they come across one, but turning that story in to a good film is another talent entirely. Luckily for Polley, she seems to possess both.