text:  ABC Entertainment News. Captain America's hidden secret power, swimming with sharks. My first time being out here in a long time. The new Captain America, Anthony Mackie, kicks off National Geographic's Shark Fest tonight with the show Shark Beach. And as a certified scuba diver for almost 20 years, he's been in the water with a bunch of sharks. Great whites in South Africa, whale sharks in Mexico, a blue whale off the coast of Cape Town.