AP Photo/National Geographic, Mark Thiessen

James Cameron, the Oscar-winning filmmaker of the two highest-grossing films of all time, can now add another major accomplishment to his list as he has now returned from an expedition to the "Challenger Deep," the deepest part of the ocean.

"Titanic" and "Avatar" director Cameron, who is also the National Geographic Explorer-in-Residence, reached the Challenger Deep in a solo dive on Monday at 7:52 a.m. local time. The depth at in Mariana Trench in the western Pacific Ocean was recorded at 35,756 feet.

Cameron planned to spent a total of six hours on the sea floor, where he collected samples for scientific research, according to the National Geographic Society. Cameron made the voyage to the bottom of the ocean in his specially designed submersible called DEEPSEA CHALLENGER.

Cameron's first words on reaching the bottom were "all systems okay," NGS reported. He returned safely to the surface in a faster-than-expected 70-minute ascent, compared to the 2 hours and 36 minute descent to the 6.8-mile-deep underwater valley, according to the non-profit institution.

"Jim came up in what must have been the best weather conditions we've seen, and it looks like there's a squall on the horizon," NASA astrobiologist and expedition member Kevin Hand told National Geographic.

Cameron' expedition was a joint research venture between the filmmaker, National Geographic and Rolex. He is expected to discuss his findings on Monday.

The filmmaker is the first to reach the ocean's deepest point since retired U.S. Navy Capt. Don Walsh and Swiss oceanographer Jacques Piccard in the bathyscaphe Trieste in 1960. Cameron is the first to complete the journey in a solo vehicle.