Theresa (Yasmine Bleeth) is an imaginative, rebellious orphan from Brooklyn, who has dreams of show business success. She tries outrageous schemes to launch herself into the public eye, until finally meeting a mentor, Sammy Cohen (Buddy Hackett), whose own career fizzled as a result of alcoholism.
Meet Joel Goodson, an industrious, college-bound 17-year-old and a responsible, trustworthy son. However, when his parents go away and leave him home alone in the wealthy Chicago suburbs with the Porsche at his disposal he quickly decides he has been good for too long and it is time to enjoy himself.
High School student David Lightman (Matthew Broderick) has a talent for hacking. But while trying to hack into a computer system to play unreleased video games, he unwittingly taps into the Defense Department's war computer and initiates a confrontation of global proportions! Together with his girlfriend (Ally Sheedy) and a wizardly computer genius (John Wood), David must race against time to outwit his opponent.
The film portrays a fictional nuclear war between NATO forces and the Warsaw Pact that rapidly escalates into a full scale exchange between the United States and the Soviet Union, focusing on the residents of Lawrence, Kansas, and Kansas City, Missouri, as well as several family farms situated next to nearby nuclear missile silos.