"Grey Dawn" is the tenth episode of Season Seven, and the 106th overall episode of South Park. It aired on November 5, 2003.
After South Park's senior citizens have mowed down more than a few farmers' markets, the residents no longer feel it's safe to be out in the streets. With their well being at stake, the boys decide to take action against the older generation. Unwilling to surrender their driver's licenses, the elderly fight back.
At the South Park Farmer's Market, Father Maxi is holding a memorial service for the nine people who died the previous day when they were run over by a senior citizen who still holds a driver's license. The proceedings are marred by another unfortunate senior related driving incident. Stan asks his father Randy why old people are still allowed to drive.
Marvin Marsh overhears his son's opinion and lets his own feelings on the matter be known, he still wants to be able to drive. Out on Stark's Pond, a man is fishing in his boat fishing until a senior couple drives their Buick off the bridge trying to find Country Kitchen Buffet and runs him over, killing him . The news covers the recent rash of senior-related driving tragedies. Marvin Marsh and the other seniors have a meeting at the community center to decide what to do. Naturally, they have trouble remembering why they are all there. They eventually remember and Marvin Marsh decides they should have a meeting. They then realize that they are having a meeting.
When Randy finds out about the meeting he realizes that when the it is over, all the seniors will be driving on the road at the same time. Horrified, Randy runs into the town and the farmer's market and shouts out a cry of alarm, causing mass panic. He asks Gerald where the boys are. The boys are playing street hockey. As Randy runs toward the boys, Kenny spots all seniors driving. Randy manages to save the boys and they flee from the many cars recklessly wandering the streets, eventually hiding in an abandoned house. Moments later, the house gets overrun by seniors making the wrong turn and going the wrong way (even on the second floor). It is later revealed that despite Randy's warning, the seniors managed to run down even more helpless victims across South Park, sparking public outrage.
The state of Colorado has demanded all seniors turn in their driver's license and the seniors are unhappy. Stan's grandfather wants Stan to accompany him, in the car, to go and pick up his new Hover Round. All the boys accompany Marvin Marsh on the trip, theorizing they'll be safer if they are in the car. Marvin's driving is at the current senior standard of bad and Officer Barbrady pulls the car over and takes Stan's grandfather to jail. Randy is reluctant to bail his father out, but his father doesn't care, the American Association of Retired Persons (AARP) is sending their aid.
Outside of his classroom, Mr. Garrison sees a large number of old people dropping out of the sky. The AARP has airdropped in reinforcements. They begin taking hostages and liberating their colleagues from the retirement home. "The revolution is on" and the AARP has taken over the town. To show they mean business, the AARP starts killing hostages.
More reinforcements arrive but then so do the Veteran military. The seniors list their demands, their driver's license's, more Medicare and keeping those kids and their skateboards off the sidewalk. The AARP leader realizes they could even take over the whole country. The children find their parents under lockup. Randy tells the boys that since they get up early, they are the only hope for getting the town back. Fleeing to the woods, the Wolverines of South Park strategize on how to save their town, their parents, and possibly the whole country. Cartman suggests attaching stolen explosives to Kyle, and then sending him as a suicide bomber to blow up the Country Kitchen Buffet. It is a restaurant so popular among elders that they are dependent on it. Stan suggests that they just lock the doors from the inside, which is exactly what they do.
The AARP plans on taking stronger action, such as killing off anyone under the age of 65 which is something even Marvin doesn't think is a good idea, but their plans are thwarted when they start starving to death outside of the Country Kitchen Buffet at 6:00 AM, just like the boys predicted. Their defenses weakened by famine, the hostages are released. Marvin is turned back over to his family. Stan sums up the lessons learned by the Marsh family today, that Randy shouldn't treat his father like a child and that Marvin should be proud to be a senior, but he should realize that he is a killing machine when he is driving. Both Randy and Marvin apologize to each other, and they all go home laughing, except the kids. As he walks off-screen, Stan mutters, "Dude, I hate my family."