When he was growing up in landlocked Niagara Falls, Ontario, James Cameron idolised the French ocean explorer Jacques Cousteau. A science fiction buff who was fascinated by space travel, Cameron found something otherworldly about the dazzling underwater imagery of Cousteau’s television specials.

“Cousteau’s shows got me excited about the fact there was an alien world right here on Earth,” he said in a 2010 Ted Talk.  

Cameron, 68, has been thinking about oceans and alien worlds ever since. In the 1980s, he directed Aliens and the deep sea epic The Abyss. Later came Titanic (1997), then the highest grossing film of all time —  until Cameron beat his own box office record with the 3D sci-fi epic Avatar, which grossed $2.8bn after its release in December 2009.