Astronomers discover a comet that they believe will crash into Phoenix, Arizona. They attempt to warn officials, but without 100% certainty, the governor of Arizona is reticent to cause a panic. Even after a television news reporter discovers the truth and threatens to go live with it, the response is understated enough to doom some residents of Phoenix to certain death.

During World War II the passenger liner "Goliath" is sunk by a German submarine. Portions of the ship's hull remain airtight, and some of the passengers and crew survive. Over the decades they build a rigidly regulated society completely isolated from the surface world until, in contemporary times, a diving team begins to explore the wreck.

Beautiful and successful television news anchor Melanie Adams falls in love with renowned heart transplant surgeon Peter Hallam. After a whirlwind courtship, they marry. Each has children from previous marriages. The strain of a new marriage and attempts to blend a family jeopardize their happiness.

Journalism Major Paxton Andrews loses the man she loves in the Vietnam War. Always having followed the beat of a different drum, she decides to work out her grief by going to Vietnam and writing a column that will hopefully help those at home better understand the War. While she's there her life is changed profoundly, and she finds new love and hope in the midst of death and destruction.