While there are many visually stunning achievements in James Cameron’s Avatar: The Way of Water, one specific mystery remained unanswered regarding the making of the film. Spider (Jack Champion) is the only human in Jake Sully’s (Sam Worthington) Na’vi family. Throughout the movie, Spider is constantly seen directly interacting with Na’vi friends and enemies alike, as well as Pandora’s jungles and oceans. However, the character blends perfectly with the computer-generated characters and environments, leaving fans wondering what Champion’s experience was like on set.

During an interview with Variety, Champion talked about what it was like for him to film his scenes for the highly anticipated sequel, which just recently became the fifth highest-grossing movie of all time. Specifically regarding what he could physically interact with on set, the actor had the following to say:

Champion’s performance also had to be captured twice due to the nature of the film’s production. During one portion of filming, he would have to read his lines off-camera. That way, he could directly interact with his fellow cast members who played Na’vi characters. During another part of the production, he would have to perform by himself with Na’vi stand-ins. The two performances were then mixed together, and the result was Spider and the Na’vi interacting as if they were in the same room at the same time.