Underwater cave explorer, Alex Alvarez, ventures into Aktun Ha with his Depthmaster 3000. Alex has been mapping the maze of submerged passageways beneath Mexico�s Yucatan Peninsula for over 20 years. As a Deep Blue Explorer and member of the Tulum Speleological Project, Alex is working with a core team of international researchers on a series of National Geographic expeditions to reveal for the first time the untold secrets hidden within the deepest, darkest reaches of the Maya underworld. Video shot, produced, and edited by Fabio Esteban Amador, March 2012.