James Cameron gets ready to dive to the Mariana Trench

in a one-man submarine, he plans to dive 11km (seven miles) down beneath the waves to the bottom of the Mariana Trench, in the western Pacific.

There has only ever been one dive there, and that was half a century ago.

Mr Cameron and his team have set sail to reach the trench and are now waiting for a clear stretch of weather to begin the dive.

The BBC met up with the director in Guam, just before he set out for the high seas. This tiny tropical island is the nearest major landmass to the Mariana Trench - the focus of Mr Cameron's ambition.

http://www.bbc.co.uk/news/science-environment-17399978