It's August 28, 1990. Mohawk filmmaker Tracey Deer is 12 years old, sitting in the front seat of her mother's car, with her little sister and two small cousins in the back.

It's the height of the Oka Crisis, and as the convoy of women, children and elders evacuating their home community of Kahnawake cross the Mercier Bridge and head into Whiskey Trench, the sunken highway entering LaSalle in Montreal, an angry mob pelt their vehicles with rocks.

"Our car — our back window was shattered. My little sister and my two cousins got covered in rocks. I was in the front seat with my mom," recalled Deer.

The scene Deer lived through at the Whiskey Trench is portrayed in the film as it happened to her in 1990. (Sebastien Raymond/EMA Films)

"In that moment, to see my mother as afraid as she was behind the wheel; to hear my sister crying in the back seat; to see people outside, gleefully cheering as they threw these rocks at us; to see police officers standing by and doing nothing to help us — that really is a moment that hatred took root in me."

This is a scene from Deer's childhood, but it's also captured exactly as it happened in her feature film, Beans.

The film, inspired by her experiences as a 12-year-old living in Kahnawake during the Oka Crisis, tells the story of a young girl nicknamed Beans set against the backdrop of the events of 1990.

Deer described that moment at Whiskey Trench, along with others from that summer, as the most traumatic of her life.

Tracey Deer is directing her first feature film based on her own experience being a little girl living in Kahnawake during the Oka Crisis. (Canadian Screen Awards)

"For me, that was such a pinnacle moment in shaping who I am. Up to that point, I didn't know hatred, to experience it or to feel it," she told CBC's Let's Go.

Deer, who won a Gemini Award for her 2008 documentary on Mohawk identity, Club Native, and wrote and directed the TV show Mohawk Girls, started production on Beans in late August, filming in Kahnawake, Kanesatake, Oka and Montreal.

The production team and cast will be hard at work until early October. The film is expected to hit theatres in fall 2020.

For Deer, who described her childhood before the Oka Crisis as "idyllic," the events of that summer mark a painful turning point.

"Once the Oka Crisis hit, the reality [hit] that my difference made life dangerous outside of the safety of my home and my community. That was a very rude awakening. It was shattering, really, to the innocence I had up until that point."

The majority of the cast are children and Deer said she took particular care to distance the young actors from the violence and hatred presented in the film. (Sebastien Raymond/EMA Films)

Her cast of actors is made up mostly of children and stars Kiawenti:io Tarbell, a Mohawk from Akwesasne, in the lead role.

Tarbell is best known for her role as Anne Shirley's Mi'kmaw friend Ka'kwet in the CBC/Netflix series Anne with an E.

Deer said that from the beginning, she knew that her film would by no means be appropriate for young audiences. So she took great care to make sure all the young actors and their families were comfortable with the subject matter.

"The last thing I would ever want would be to be recreating the most traumatic time of my life and be traumatizing anyone in the process," said Deer.