TERRA EPISODE 216/217 PREVIEW: Glide along through the sparkling blue waters of the South Pacific with the ocean's greatest performers - the Spinner dolphins. The show goes on underwater too where Spinners work together to eat, sleep, and keep each other safe from predators. Join scientists in Hawaii, Tahiti, and French Polynesia on a journey of a thousand bellyflops and learn how you can make a difference in the lives of these spectacular OCEAN ACROBATS.