If not for surveillance video, residents of a street in the Preston part of Cambridge might never have known exactly what happened to their cars.

Patrick and Jessica Douglas were awakened around 5 a.m. Tuesday by a phone call from their neighbour, who told them what had just taken place.

“A truck came and hit my car, which then hit my husband’s car. (It) also hit my neighbour’s car,” Jessica says.

The neighbour’s surveillance footage shows a truck suddenly zooming into the frame, then leaving the Dolph Street roadway and ending up on the Douglas’ lawn, where it almost hit a tree before smashing into the car, righting itself, and driving away.

“I don’t understand how somebody could do something like that,” Jessica says.

Jessica’s car received dents to two doors, and had its back window smashed out. Patrick’s received damage to its windshield, front and back bumpers, and taillights.

The surveillance camera had been installed less than 24 hours before the crash.

Patrick says that’s not the only stroke of fortunate timing around the collision, as most days he would have been outside shoveling at the time of the crash – potentially putting him right in the path of the truck.

“I took the week off work for March Break, and I’m counting my blessings,” he says.

With reporting by Allison Tanner