James Cameron's Mariana Trench dive: First video footage

Director James Cameron completed his trip to the Mariana Trench, the deepest part of the world's oceans on Sunday (March 25). Now National Geographic is releasing a teaser video of what the famed filmmaker saw...and it's remarkable.

Cameron went nearly seven miles under the Pacific Ocean surface as part of National Geographic's DeepSea Challenge program. The dive, and all that went into it, will soon be turned into a special and released to the public.

The Oscar winner is no stranger to hanging out on the ocean floor. As part of making "Titanic," Cameron took 12 trips to the famed ship wreck site at the bottom of the North Atlantic.

Here's the video that National Geographic is putting out now. It's certain there will be hours more where this came from.