Fourteen-year-old Leo Beiderman (Elijah Wood) did not expect to make an earth-shattering discovery when he joined his high school astronomy club. He didn’t expect to make any discoveries at all; he simply hoped that classmate Sarah Hotchner (Leelee Sobieski) would discover him. Yet a photograph he takes through his small telescope makes him co-discoverer of Comet Wolf-Beiderman … a comet that scientists determine is on a fatal collision course with the Earth.

In the weeks and months that follow, not only these few individuals but everyone in the world must struggle to find meaning for their lives in the face of looming catastrophe. A plan is set in motion to establish underground shelters, “Arks,” in which a fortunate few may survive the impact even if all other life on Earth is wiped out. As the day of cataclysm grows nearer, all the range of human reactions is evoked — from panic to noble resignation to fate.