Jim Adams, a biological scientist who begins to take stock of his hitherto unsatisfactory career and achievements. During a flight home from Japan via Australia, his plane crashes on an island in the South Pacific leaving Adams the sole survivor, or so he thinks. He survives as best he can, pondering for the first time the true meaning of life. As a rationalist he shuns the concept of "God" instead coming to the conclusion that there must exist a Mysterious Creator, or "MC". He meets another survivor on the island, a well-educated Japanese engineer called Tadeo who is, to Adams' surprise, a Roman Catholic. After adventure and conflict their relationship matures, and together they continue Adams' philosophical investigation. Adams turns from philosophy to religion; he loses his cynical materialistic outlook, learns to pray and allows his spiritual life to flourish. After several failed attempts he and Tadeo providentially escape from the island.