The novel opens with the family in the hold of a sailing ship, weathering a great storm. The ship's passengers evacuate without them, and William and Elizabeth and their four children (Fritz, Ernest, Jack and Francis) are left to survive alone. As the ship tosses about, the father - William - prays that God will spare them.The ship survives the night and the family finds themselves within sight of a tropical desert island. The next morning, they decide to get to the island they can see beyond the reef. With much effort, they construct a vessel out of tubs. After they fill the tubs with food and ammunition and all other articles of value they can safely carry, they row toward the island. Two dogs from the ship named Turk and Juno swim beside them. The ship's cargo of livestock (including a cow, a donkey, two goats, six sheep, a ram, a pig, chickens, domestic ducks, domestic geese, and domestic pigeons), guns & powder, carpentry tools, books, a disassembled pinnace, and provisions have survived.