Nature: Shark Mountain

Located midway between the Galapagos Islands and the Pacific coast of Costa Rica, Cocos Island is a tropical paradise dotted with rugged cliffs, majestic waterfalls, lush rain forests, and white sand beaches. Its turquoise waters are home to a stunning variety of marine life, including one of the world's most fertile breeding grounds for hammerhead sharks. Husband-and-wife nature photographers Howard and Michele Hall reveal Cocos Island's dazzling display of underwater life in this special episode of PBS's award-winning NATURE series.