Cutting-edge underwater photography combine with state-of-the-art graphics to reveal the raw drama of the conflicts, subterfuge, battle plans and attack tactics of sharks. Techniques employed in BBC's "Predators" are used, this time in a new theatre of war - an underwater battleground that plays host to nature's version of submarine warfare. It maps the terrain, identifies the targets and follows the hide-and-seek battle tactics as they unfold. And it captures the extraordinary battery of senses at a shark's disposal, revealing how they use them to locate and home in on prey.