After their 43-foot schooner was stove in by a pod of killer whales, the six members of the Robertson family spend 37 days adrift in the Pacific with no maps, compass, or navigational instruments.They use every survival technique they can as they battle 20-foot waves, marauding sharks, thirst, starvation, and exhaustion.

Brian comes under the addictive spell of a parasite with the ability to induce euphoric hallucinations in its hosts.