This fascinating documentary by Sarah Polley — the superb Canadian actress who directed the wonderful old-age drama “Away From Her’’ — starts out with her elderly father and siblings remembering the mother who died of cancer in 1990, two days after Sarah’s 11th birthday.
The film’s first half-hour is given over to fond reminiscences of Diane Polley, a vivacious actress and minor Canadian celebrity who’s vividly portrayed in newly staged “home movies’’ by Rebecca Jenkins.
There are hints, though, that Diane had marital problems with Sarah’s dad, British-born actor Michael Polley.
After Diane’s death, as Sarah entered adolescence, family members recall recurring “jokes’’ around the dinner table that Michael might not actually be the father of the red-haired Sarah, to whom he bears little resemblance.
As part of this intensely personal documentary, Sarah interviews her mother’s friends, who reluctantly recall Diane’s fateful separation from Michael in 1978, when she was performing for two months in a play in Montreal.
Though Michael and others say the absence ultimately brought the couple closer together, she was also pregnant at the age of 42.
Diane, who was concerned about giving birth to a baby with Down syndrome, changed her mind about an abortion, and Sarah was born in 1979.
Decades later, her mother’s friends volunteer the names of two men — an actor who performed with her in the play and a somewhat pompous film producer — who might be Sarah’s father.
Should Sarah and the potential father undergo a DNA test? What will be the impact on Sarah’s dad and her grown siblings — some of whom turn out to be from an earlier, unhappy marriage of Diane’s?
Sarah’s birth father argues that the function of art is to get at the truth, but “Stories We Tell’’ questions the very possibility of this.
The various witnesses tell contradictory tales that turn this into a real-life “Rashomon.’’
The fact that two of the principals — Sarah and Michael, who delivers touching and eloquent on-camera narration that he wrote himself — are accomplished actors adds another level of confusion and interest that help make this compelling storytelling.