Trapped on board a runaway hot air balloon, Larry and Balki must find a way to get back to Earth as Jennifer goes into labor.
Jennifer is two weeks overdue and has a few false alarms. Meanwhile, After Balki and Mary Anne went to the fair, Mary Anne goes into labor and has her baby in the driveway. Jennifer is told about a balloon ride Mary Anne went in and in hopes of going into labor, Larry and Balki take Jennifer up in the balloon.
When all of Balki's ants on his farm die, He discovers that he has the ""exterminiki curse"" and everything he touches will instantly die. So he must wear an oven-mitt suit but can't do his job and drive Jennifer and Mary Anne away until the curse is over.