Ending

[deleted]

Trying to escape from Hell's version of Hamilton High, Alex and Sarah run to the school's autoshop, get into one of the Fifties-period cars, and start frantically searching for the keys. The condemned souls/zombies of Mary-Lou's victims gather round the vehicle, smash the windows and begin reaching inside. Sarah hot-wires the car, Alex starts it up and drives straight at Mary-Lou, who has reappeared directly in front of them. The car hits her, and both Mary-Lou and the vehicle (together with Alex and Sarah) vanish in a blaze of light.

Alex and Sarah find themselves back in the real world, driving down a quiet road. Alex pulls over at a closed-down diner in order to use the pay-phone on the outside of the building to call his parents. He asks Sarah if she has any change, whereupon Sarah is suddenly stabbed through the seat by Mary-Lou, who's in the back of the car. Sarah dies. Looking about, Alex sees that the diner is suddenly open, with other Fifties-period cars parked alongside, and customers & waitresses in Fifties clothes. Realising that Mary-Lou has used her powers to send him back in time, Alex starts laughing insanely and tells Mary-Lou that she's won.