The "Avatar" sequels are still an unknowable white whale. Not even star Sam Worthington has any real idea what James Cameron has planned for a return to Pandora, though at least he was privy to news about Cameron's Mariana Trench dive.

"Yeah, I've know about his expedition for years," Worthington told The Huffington Post this week. "The Mariana Trench: No one knows what's down there! I don't think he's going to come back. I think there's a sea monster."

Spoiler alert: there wasn't, but Cameron's dive did provide the director with some guidance for further "Avatar" adventures.

“The best inspiration I got for ‘Avatar’ 2 and 3 was dealing with the master navigator culture in Micronesia,” Cameron told the Los Angeles Times.

Cameron spent seven years preparing for his historic dive on many of the Western Pacific islands; the Micronesians are famous for their instrument-free deep-sea voyaging.

Of course, even with that creative spark, don't think Cameron gets all his ideas from ocean exploration.

"When I’m doing deep ocean exploration, I’m doing deep ocean exploration and when I’m making ‘Avatar,’ I’m making ‘Avatar,'" he said.

"Avatar" is the highest grossing movie of all-time. Release in December of 2009, it earned more than $2.7 billion worldwide. The sequels were initially due out in theaters in December of 2013 and 2014, respectively. Producer Jon Landau recently said that 2016 could be more realistic. For more on Cameron's dive, check out the slideshow below.

[via LAT/Hero Complex]

GALLERY: PHOTOS OF CAMERON'S DIVES

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  • This February 2012 file photo provided by National Geographic, shows explorer and filmmaker James Cameron emerging from the hatch of DEEPSEA CHALLENGER during testing of the submersible in Jervis Bay, south of Sydney, Australia. Cameron on Sunday, March 25, 2012 began his journey to someplace only two men have gone before �-- to the Earth's deepest point. The director of "Titanic," ''Avatar" and other films is using the specially designed submarine to descend nearly seven miles (11 kilometers) to the bottom of the Mariana Trench, an area 200 miles (320 kilometers) southwest of the Pacific island of Guam. (AP Photo/National Geographic, Mark Thiessen, File)

  • In this photo provided by National Geographic, filmmaker and National Geographic Explorer-in-Residence James Cameron gets a handshake from ocean explorer and U.S. Navy Capt. Don Walsh, right, just before the hatch on the DEEPSEA CHALLENGER submersible is closed and the voyage to the deepest part of the ocean begins, Sunday, March 25, 2012. Walsh took the same journey to the bottom of the Mariana Trench 52 years ago in the bathyscaphe Trieste with Swiss oceanographer Jacques Piccard. Cameron is the first person to complete the dive solo. The dive was part of DEEPSEA CHALLENGE, a joint scientific expedition by Cameron, the National Geographic Society and Rolex to conduct deep-ocean research. (AP Photo/National Geographic, Mark Thiessen) MANDATORY CREDIT

  • In this photo provided by National Geographic, the DEEPSEA CHALLENGER submersible carrying filmmaker and National Geographic Explorer-in-Residence James Cameron is hoisted into the Pacific Ocean on its way to the "Challenger Deep," the deepest part of the Mariana Trench, Sunday, March 25, 2012. The dive was part of DEEPSEA CHALLENGE, a joint scientific expedition by Cameron, the National Geographic Society and Rolex to conduct deep-ocean research. (AP Photo/National Geographic, Mark Thiessen) MANDATORY CREDIT

  • This February 2012 handout photo provided by National Geographic shows the DEEPSEA CHALLENGER submersible begining its first test dive off the coast of Papua New Guinea. Earth's lost frontier, the deepest part of the oceans where the pressure is like three SUVs sitting on your little tow, is about to be explored first-hand. It's been more than half a century since man dared to plunge that deep. Earth's lost frontier is about to be explored firsthand after more than half a century. It's a mission to the deepest part of the ocean, so deep that the pressure is the equivalent of three SUVs sitting on your toe. And it's being launched by the rich and famous. In the next several days, James Cameron, the director of �"Titanic,�" �"Avatar�" and �"The Abyss,�" plans to dive nearly 7 miles deep in a one-man sub he helped design. The location is the Mariana Trench in the South Pacific. �"It's the last frontier for science and exploration on this planet,�" Cameron said. (AP Photo/Mark Thiessen, National Geographic)

  • In an image provided by National Geographic filmmaker James Cameron gives two thumbs-up as he emerges from the Deepsea Challenger submersible Monday March 26, 2012 after his successful solo dive in the Mariana Trench, the deepest part of the ocean. The dive was part of Deepsea Challenge, a joint scientific expedition by Cameron, the National Geographic Society and Rolex to conduct deep-ocean research. (AP Photo/Mark Theissen, National Geographic)

  • Filmmaker and National Geographic Explorer-in-Residence James Cameron emerges from the Deepsea Challenger submersible after his successful solo dive to the Mariana Trench, the deepest part of the ocean, Monday March 26, 2011. The dive was part of Deepsea Challenge, a joint scientific expedition by Cameron, the National Geographic Society and Rolex to conduct deep-ocean research. (AP Photo/Mark Theissen, National Geographic) ONE TIME USE

  • In a photo provided by National Geographic filmmaker and National Geographic Explorer-in-Residence James Cameron holds the National Geographic Society flag after he successfully completed the first ever solo dive to the Mariana Trench Monday March 26, 2012. The dive was part of Deepsea Challenge, a joint scientific expedition by Cameron, the National Geographic Society and Rolex to conduct deep-ocean research. (AP Photo/Mark Theissen, National Geographic)

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