After flying back from 1931, Marty McFly crashes into a billboard depicting an alternate Doc, who is in charge of Hill Valley. After getting out of the car with the help of an alternate version of Jennifer Parker, in this timeline, a punk rock vandal who wants nothing to do with Marty, the DeLorean falls out of the billboard, damaging it. By salvaging one of the DeLorean's hoverwheels and its Mr. Fusion battery (which is only 12 volts) Marty is able to jump over the wall into an alternate Hill Valley, a seemingly utopian crime-free town.