We'll marvel from the safety of an underwater iron cage as the incredible Hawaiian mano (sharks) rise from the depths of Oahu's North Shore just to greet us, their entrancing beauty and splendor literally at our fingertips. We'll board an efficient 32-foot (9.8 m) aluminum boat, head out to sea on a 2-hour journey that promises plentiful close encounters of the aquatic kind - watching the rolling waves along the way for greetings from dolphins, Hawaiian green sea turtles and - in the winter months - humpback whales. Then we will climb into the submerged steely fortress and experience the sheer exhilaration of sleek 5- to 15-foot (1.5 m to 4.6 m) sharks swimming mere inches from us and a few fellow cage-goers.