Billionaire investor Ray Dalio and "Avatar" filmmaker James Cameron back the submarine company Triton Submersibles. The company offers submersibles that cost between $2.5 million and $40 million.

"Titanic" director James Cameron speaks out after the missing sub tragedy. He said he was "struck by the similarity" of the submersible to the Titanic disaster.

Inside James Cameron’s Billion-Dollar Bet on ‘Avatar ... In 2012, tucked inside the 43-inch-wide cockpit of a submarine he designed with the National Geographic Society, ...