When Bart is forced to assist Principal Skinner during a long night of astronomy, he discovers what appears to be a giant comet heading towards Springfield. A call to the astronomers at the observatory confirms that a comet is indeed hurtling towards Springfield at an alarming rate, and will more than likely kill all of the town's residents when it crashes. Scientists fail in their efforts to throw the comet off course and the entire town goes hysterical as the flaming ball continues along its course of destruction. Luckily for everyone, Ned Flanders has enough room in his family's bomb shelter for most of the town, but when the quarters become too cramped, one person must be expelled and risk being killed by the comet. Who will it be and what will happen to him or her once the comet crashes?
