Nothing was off-limits for James Cameron while filming Avatar: The Way of Water, including the idea of whale motion-capture co-stars.

In a Variety exposé, Cameron spoke about how his passion for oceanography influenced various creature designs in the director's long-awaited sci-fi blockbuster sequel. One such underwater inhabitant, whale-sized beasts called tulkuns, lead to a question on whether Cameron actually used live whales to capture a tulkun's physical movements in digital form. "You know, everybody leaned into [the film-making process]," he said, recalling, "I think we even looked at possibly shooting in the real ocean with performance capture. We looked at it, but everybody's production instinct said, 'You know, we're gonna regret that.'" Instead, according to producer Jon Landau, Cameron imitated the feel of a whale by "having one of the film's troupe members move around a crude model of a tulkun in the water while vocalizing whale noises."

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Another aquatic Way of Water creature, the plesiosaur-inspired Ilu, was brought to life using practical models. As told in the exposé, Cameron's team placed these models -- capable of traveling 15-20 miles per hour -- in the water and let his cast ride them while filming key scenes of the movie. "It's pretty dramatic," Cameron continued, admitting that the models "didn't really look as much like them, but they performed just like them."

Avatar: The Way of Water Generates Buzz Ahead of Release

Despite coming out 13 years after the first Avatar, early Avatar: The Way of Water reviews have been largely positive. Praise has gone to not only Cameron's groundbreaking visuals and world-building elements, but its emotional story and relationships between Jake Sully, his wife Neytiri and their Na'vi family. At a press conference, Cameron assured critics that The Way of Water's "story goes much deeper in terms of heart and emotions," listing some of its inspirations as "parents and the family dynamic, the responsibility of having kids and what it's like from a kid's perspective."

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Details about Sully's plight were teased during The Way of Water's latest trailer, previewing his family's underwater adventures and new robotic foes created by the Resource Development Administration. Another threat is formally deceased villain Colonel Miles Quaritch who, according to actor Stephen Lang, has been reborn as a Recombinant, or "genetically-engineered autonomous avatar" for the RDA. Financially, the movie expected to make between $150 million and $175 million during its opening weekend -- with some sources even optimistically predicting $200 million -- all records that exceed the original Avatar's opening box office numbers.

Avatar: The Way of Water opens in theaters on Dec. 16.

Source: Variety