When the first Avatar movie came out in 2009, James Cameron’s use of performance capture technology astonished the film industry and fans with its ability to transform actors into never-before-seen creatures. Avatar: The Way of Water features even more performance capture technology, manipulating the actors’ appearance as they performed underwater for many of the key scenes – and even the water is computer generated.

In an interview with IndieWire’s Awards Spotlight series, Sigourney Weaver and Sam Worthington discussed their work within the performance capture method under Cameron’s direction.

“I don’t think that performance capture replaces acting,” Worthington, who returns to his role as Jake Sully in the sequel, said. “Actors shouldn’t be scared of it. It actually just opens up more possibilities of characters you can play. That’s what our job is, to step into other characters, whether it’s a marine who’s now driving a nine-foot-tall alien body or a 14-year-old, or a whale.”

Weaver, who played human researcher Dr. Grace Augustine in the first movie, now portrays Na’vi teenager and Jake and Neytiri’s adopted daughter, Kiri. The 72-year-old actress spent a great deal of time perfecting teenage mannerisms to craft her performance. Weaver added:

“There are all these myths that scare actors… If anything, this experience makes me realize they need us more than ever. We are not voicing these characters. We’re not animating these characters. We are the soul of these characters — and that is what this technology picks up.” She continued, “They need us more than ever.”

“I yielded to whatever Sigourney was giving me,” Worthington noted on their performance. “I didn’t have any judgement at all. To me, she was Kiri. Whether it’s in mo-cap or someone in prosthetics, if an actor is bringing you a character who’s fully defined, it makes the work a whole lot easier.”

Both actors were quick to dispel any notions that the technology outshined their skills and emphasized the incredible synthesis between their performances and the capture.

“These pictures are demanding in a different way,” Weaver said. “That’s why they need such good actors to come alive.”