As the S Club 7 travel down a deserted highway in the middle of nowhere, they notice that the odometer on the Chevy is about to go from all nines to all zeros. When the big moment comes, they're a bit let down because nothing special happens, but what they don't realize is that something DID happen. The car passes through an invisible timewarp that takes the band back 40 years to 1959.
As they try to find a way back to 1999, they meet up with Chuck who works at his dad's restaurant, the Big Cup Diner, and who Hannah has a crush on. Then, they have a run-in at the bowling alley with a gang called The Rockets, which is lead by a jerk named Ricky, and Jo, Bradley, Paul, and Rachel get arrested and spend the night in jail.
After getting out of prison, the band have a big party at the diner to help out Chuck and his dad, but then they have to leave town immediately before the nasty sherriff catches them or face going to jail again. They come back to town the next day, or so they think. Chuck tells them that they've actually been gone a month, and that Ricky and his gang have been trashing the diner ever since.
When they hear all about the feud between Ricky's and Chuck's dad, the S Club decide to teach Ricky a badly needed lesson. They enter a car race against him with Rachel driving the Chevy, but before the race starts, Chuck is found in the car, preparing to do battle with Ricky. Hannah warns him not to drive in the race, and shows him a newspaper article from the next day's issue, about how he gets killed in the race.
Eventually, with Rachel behind the wheel, the S Club end up beating Ricky, and his and Chuck's dad decide to go into business together. Having completed their mission, the S Club leave town, and go back through the timewarp. As they continue to drive, they enter the town again, but this time they're back in 1999, and a few things have changed. Chuck is now a renowned politician, Ricky's gotten older and fatter, and the Big Cup Diner has been renamed as the S Club 7 Diner in their honor.