A jaded pilot named Noah Dugan is unemployed and owes a large amount of money due to his gambling. He goes to an old friend, Stoney, who owns an airfield. He is offered a job flying a cargo of animals to a remote South Pacific island aboard a
B-29 bomber, a large plane well past its prime. Bernadette "Bernie" Lafleur is the primary missionary who accompanies him, although they initially dislike each other. Bernie has raised the animals at an orphanage and is close to two of the orphans, Julie and Bobby, who resents Dugan after seeing him mistreat one of the animals. As the aircraft prepares to taxi for takeoff, Bobby is concerned about Dugan's treatment of the animals, and decides to stow away aboard the bomber so that he can make sure they are properly cared for. Julie follows Bobby aboard. During the flight, the bomber goes off course, and, running low on fuel, Dugan is forced to crash-land on an uncharted island that Bobby spotted. While on the island, the group meets two elderly
Japanese holdout sailors who have lived there alone for 35 years. Dugan is suspicious of them, as the sailors are unaware that World War II is over, but Bernie wins their friendship and trust. She learns that one of them is named "Cleveland", after
the American city by his mother, who had spent time in America before the war and taught him English, allowing the two groups to communicate. The sailors convince Dugan and Bernie that there is no hope of rescue should they stay on the island, as the two had been there for decades with no one coming to repatriate them. They propose a plan to turn the old aircraft into a boat to sail back to civilization. This requires flipping the B-29 upside down, as this will be a more stable and watertight configuration, and sewing a sail for propulsion, which Bernie volunteers to do. The Japanese sailors give her their
battle flag of the Japanese Empire, which she uses as the primary fabric for the sail. As they work on the plane, Dugan and Bernie begin to warm up to each other and fall in love. Bernie paints the name ''"Noah's Ark"'' on the converted aircraft, after Dugan's first name, much to his chagrin, though he eventually accepts it. At Bobby's insistence, the animals are brought aboard, and ''"Noah's Ark"'' and its crew set sail. After many days at sea with no civilization in sight, Bernie, inspired by the story of
Noah's Ark and the dove which returned with an olive branch, suggests sending a duck with message attached, telling of their need for rescue. However the duck flies westward, away from the direction of Hawaii, and hope dwindles. Bobby falls overboard while trying to fish, but Dugan, who has formed a bond with him, saves the boy from a large shark circling the boat. Eventually, they are rescued by
United States Coast Guard Cutter Mellon, which has the duck aboard, and the
Ark is towed to Oahu. ==Cast==