While cruising the South Seas with friends aboard a sailing yacht, it is wagered that Steve can not survive on a desert isle without the accouterments of civilization. After accepting the wager, Steve and his dog swim ashore and begin to recreate their Park Avenue world by way of various 'Rube Goldberg' type contraptions constructed from local materials. Meanwhile, on a nearby island, a young maiden flees her arranged wedding. She canoes to Steve's island for safety, whereupon she is dubbed "Saturday". Soon they are attacked by vengeful tribesmen from the neighboring island. Will Steve and Saturday survive?