Andy Serkis has been the face (or many faces) of motion capture technology over the past 15 years. As an actor, he helped pioneer the art during the Lord of the Rings movies, and then imbued the technologically stunning simians of the Planet of the Apes trilogy with a distinct humanity. Now, Serkis has ascended to the director's chair, and in Mowgli, his upcoming adaptation of Rudyard Kipling's The Jungle Book, he takes another step toward integrating computer graphics and intangible human spirit.

"It's one thing to digitally create a photo-real tiger, but if you just add a voice that you recorded in a booth, that's just not gonna work because there will always be a disconnect between those two," Serkis told SYFY WIRE last week. "So what we decided to do is to design the animals around the faces and physiognomies of our actors."

Serkis, who also acts in the movie as the bear Baloo, asked some of Hollywood's biggest names — Christian Bale, Cate Blanchett, Benedict Cumberbatch — to slip on motion capture suits. Every actor cast as an animal performed the part with those thousands of dots on their faces and head-mounted cameras recording their every movement, a process that took three full weeks to complete. They acted on sets meant to approximate the ones they were building on other soundstages, and acted opposite Rohand Chan, the young actor who plays Mowgli.

Then came a phase of digital artistry that, for the less technically inclined, sounds a little bit like the '90s kids book series Animorphs.

"We'd start off with the image of one of our actors, say Christian Bale, and then the image of a panther that we were heading towards," Serkis explained. "And then we'd literally morph Christian's face progressively along sort of a line, and then towards a panther. Then you'd find a sweet spot on that spectrum, and that became the basis for the creatures."

This isn't entirely novel. In the Planet of the Apes films, features from Serkis's performance-captured face were worked into Caesar's visage. Disney's 2016 version of The Jungle Book used motion capture on a few actors' faces, but also referenced photographs, all in service of making slight tweaks to the animals.

As Mowgli's first trailer shows, Serkis' more complete approach created a series of distinct hybrids, animals that look remarkably realistic in some respects and more believably anthropomorphic in others. The eyes are bigger, faces more inviting, and bodies humming with the essential minor details that we take for granted in living creatures.

"if you just have pure animation and it looks photoreal, and then you add a voice," Serkis said, "what you don't get is all of the breath, all of the movement, all of the idiosyncratic little beats and choices that the actors make."

Serkis had jungle sets built inside the sound stages where the film was shot, with dead wood and underbrush brought in to line the ground. It added another element of reality — Jon Favreau filmed the 2016 Jungle Book entirely on green screen sets — and then it was off to filming in the actual real world, as the production shifted to South Africa to film scenes with actors such as The Americans' Matthew Rhys.

ROHAN CHAND as Mowgli in Warner Bros. Pictures’ action adventure “MOWGLI,” a Warner Bros. Pictures release. Photo Courtesy Warner Bros. Pictures

This adaptation of Rudyard Kipling's novel, as befitting the "darker" nature promised by the filmmaker, will directly touch on the context in which it was written: The British occupation of India.

Published in 1898, the book has been both heralded as a great classic and the product of imperialism that reflects the racist attitudes of the time. Serkis suggested that the film doesn't shy away from the imperialist themes of the book, without actually endorsing them.

"That fabric and the complexity of Rudyard Kipling as a writer and what he represented," Serkis said. "I mean, to some people, he was one of the most beloved British authors of a generation. But others considered him quite frankly a racist and a colonialist. So that texturing and layering is in the film, the world of Kipling as well as the stories that he's written. It's the time that he wrote it, really informs all that."

Mowgli hits theaters on October 19.