This is one of the funniest episodes of South Park ever. My most favorite part is Randy Marsh yelling, "Get off the streets! Old people are driving!!" And then he brought the boys to safety in an old house. So many seniors driving their cars are everywhere. They keep crashing in, but Randy and the boys manage to avoid the car attacks. After taking away their licenses, old people from A.A.R.P., the American Association of Retired Persons, take over the whole city of South Park. It was all up to the boys to save everybody.
I was laughing really hard while watching old people driving and killing other people. Stan's right that his dad shouldn't treat his grandpa like a child, and made his grandpa realize that when he gets behind the wheel, he's a killing machine.