This is the moment a motorcyclist good samaritan reunites a forgetful driver with her coffee cup - after plucking it off her SUV while speeding down an American highway.
The mystery biker is filmed tearing down the highway when he spots the small white cup perched perilously on the back left bumper of a vehicle a few metres ahead.
The motorcyclist wastes no time before accelerating alongside the vehicle and snatching the errant cup.
In his determination to return the kitchenware to its absent-minded owner, he follows the SUV around a corner in Orem, Utah, and waves it towards their window.
The woman initially fears she is being pursued by a threatening motorcyclist, and attempts to drive away at first.
Several hundred metres later the driver spots the biker holding the cup and gratefully takes it back.
The biker captured the whole incident on a helmet cam he was wearing as he sped alongside the motorist.
His good deed done, the motorcyclist speeds off in the distance, as the driver empties the cold contents of the cup out of the window.