In hand-built, double-hulled canoes sixty feet long, the ancestors of today's Polynesians sailed vast distances using only the waves, the stars, and the flights of birds to navigate. Anthropologist Sanford Low visits the Caroline Islands of Micronesia to meet Mau Piailug, the last navigator initiated on his island and one of few men still practicing this once-essential art. He demonstrates his skill by sailing a replica canoe 2500 miles from Hawaii to Tahiti with no modern navigational instruments.