After her boyfriend Mike cancels their anniversary date, seventeen-year-old Chris Parker invites her friend Brenda over to her Oak Park, Illinois, house to cheer her up, but is convinced by her mother to babysit the Andersons’ daughter, 8-year-old Sara, while they attend a party in downtown Chicago. Fifteen-year-old Brad Anderson is supposed to go to his friend Daryl Coopersmith’s house to spend the night, but he changes his mind when he finds that Chris is the sitter. After receiving a frantic phone call from Brenda, who ran away to the bus station downtown, Chris plans to go alone to pick her up but is coerced by Brad, Sara, and Daryl to take them with her. On the freeway, their station wagon suffers a flat tire and they are picked up by a tow truck driver,
