Fillion slowed down when he saw the nearby river had spilled its banks, but his car still got swept away and he ended up in a ditch. At first it seemed like a minor accident, but then he felt the car "rock from one side to the other."
That's when he started to panic.
The rushing water carried Fillion and his car several hundred metres.
He called his family and then 911.
Fillion thought he might die at that moment.
"Your life passes in front of you, and you think of all the good things you've done," Fillion recalled.
"You just say to yourself, 'If I get out, I'll make sure to do more.'"
Fillion said his car finally stopped when it got snagged on a little bush. He was able to make it out of his car through the sun roof.
But firefighters at the scene couldn't see him, and couldn't hear his cries for help over the sound of the rushing current.
It was the flashlight on his phone that finally attracted their attention.
Moments later, Fillion said they were on their way to rescue him.
Heavy rain earlier this week has caused major flooding in parts of Quebec's Eastern Townships, sweeping away cars and forcing people to seek emergency shelter.
More than 80 mm of rain fell on Tuesday in Coaticook, with the majority of the rainfall coming in a short period of time.