When World War II began, the U.S. Navy was unprepared to enact its island-hopping strategy to reach Japan. Anticipating tides, planning for coral reefs, and preparing for enemy fire was new ground for them, and with lives at stake it had to be figured out quickly. In this history, Catherine Musemeche explains why they turned to marine biologist Mary Sears, who—along with a team of quirky scientists—helped to turn the tide of the war in the United States' favor by clearing a path to Okinawa, the last major battle of World War II.