Ahead of the debut of AMC's 'Visionaries: James Cameron’s Story of Science Fiction,' the director opened up his personal museum of props from 'Titanic' and 'Avatar.'

James Cameron famously declared he was “king of the world” on the 1998 night when his blockbuster Titanic took home 11 Oscars. Two decades later, little has changed: two of his films (Titanic and Avatar) rank as the all-time highest-grossing worldwide releases; he’s hard at work on multiple Avatar sequels; and he has a new AMC docuseries, Visionaries: James Cameron’s Story of Science Fiction, that explores the origins of the genre premiering April 30.

In the six-part docuseries, Cameron sits down with a number of his contemporaries — directors Steven Spielberg, George Lucas and Ridley Scott as well as Terminator star Arnold Schwarzenegger — to discuss their impact on science-fiction and other topics including what inspires them. The series also features interviews with Will Smith, Sigourney Weaver, Westworld co-creators Jonathan Nolan and Lisa Joy, Stranger Things masterminds the Duffer brothers and more.

Cameron isn’t just trying to appeal to hardcore genre fans with the AMC series, whose entire run is available now via its subscription service. “The target audience is very broad. [It includes] people who aren’t necessarily sci-fi fans [and] may not have grown up knowing all the literary references,” he told reporters during a recent tour through his personal collection. “What was important to me on this series was to trace back the DNA of the ideas.”

With Avatar 2 and 3 well into production and occupying three-and-a-half soundstages on the Manhattan Beach Studios lot, Cameron found himself with a half-stage left over. It was too small to use for production, but too much space to simply waste. So he moved many of his bigger props into the space, rotating them out when they’re needed elsewhere. (The Australian National Maritime Museum is opening up an exhibit with his artifacts from Deepsea Challenge 3D next month.)

Here, Cameron shares behind-the-scenes details about some of his most memorable props.

Spoiler alert: it took movie magic to make this Avatar piece work. “We put in Stephen Lang, pulled the arms and legs off, and had it walk around using CG in the movie,” Cameron says. “This was just a physical prop for him to climb in and out of.”

Although Avatar's Na’vi were digitally rendered, the team had to build a physical replica of any objects they handled first. By doing that, “we could understand how it would sit on the body,” Cameron explains. “How when somebody moved it would pinch the skin, or if it floated or flopped around when somebody moved quickly. You need to understand the [real] physics of it and get the texture [right].” The necklaces and chest pieces were crafted by “weavers and indigenous artists that worked for Weta workshop in New Zealand.”

Cameron, a diehard Titanic buff, owns a working model of the ill-fated ship's engine that is powered by crank. His film also used a “much larger model” that they discovered in a 1930s-era ship in San Francisco. “We put in little railings and things in the real ship’s engine and turned it into a one-third scale functioning model,” he recalls. “The set was full scale, but the Titanic wasn’t as big as we imagined it. So I never cast any actors who were over 5-foot-9. You immediately lose like $5 million of production value by putting a tall guy on the set!”

The infamous steamy handprint in the car after the love scene between Jack (Leonardo DiCaprio) and Rose (Kate Winslet) is still faintly evident on Titanic car, but that's not the biggest surprise — it’s actually Cameron’s hand. “The second the steam evaporated, we needed to match continuity,” he explains. “So we just took some spray [to help it stick] … that’s why it’s still here.”

In addition to a model of the pre-iceberg Titanic, Cameron has a re-creation of its wreckage that is currently mid-renovation after it was damaged in shipping. The director has big plans when they’re done with it. "We’re using our video and photographs from [our] expedition to actually make it the most accurate model of the wreck in existence. We’re most of the way there. We’ve reconstructed most of the foredeck. We’re working on the sides and the back now."

Cameron has been careful to not overrun his own home with props, but the Titanic ship wheel used to reside in his office. “Working on a movie always feels like you’re a captain of a sinking ship!” he jokes.

Cameron's Visionaries bows Monday at 10 p.m. on AMC.