In ‘Alien: Romulus,’ Xenomorphs and Facehuggers Walk Into a Zero-Gravity Elevator…

For “Alien: Romulus,” director Fede Álvarez was able to make the iconic Xenomorphs and Facehuggers even more badass than in Ridley Scott’s masterful “Alien” (1979). And he did so even while adhering as closely as possible to H.R. Giger’s original designs (with minor exceptions for heightened emphasis) since his re-imagining takes place between “Alien” and “Aliens” (1986) on an abandoned research station.

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Álvarez also shot as much as he could practically in camera, relying on suits, animatronics, and puppets from Legacy Effects. This was part of the tactile vibe, and it was key for the actors to have creatures to play against and react to. Thus, the physical effects (supervised by Alec Gillis) worked seamlessly with the fast-moving, action-packed VFX (production supervised by Eric Barba).

“It’s really when the Facehuggers or the Xenos have to move in ways that a puppet, or a guy in a suit, or animatronic Xeno couldn’t, where we would then use our CG Xenos,” Barba told IndieWire. “Or in cases where you’re doing multiple things that you just couldn’t do with the practical.”

As great as the effects were in the original “Alien,” the limitations were apparent by the shots of the Xeno lasting about half a second. That’s because it was a man in a suit, and mobility was limited. But Álvarez wanted his Xeno to truly seem like a predator. Body language was important, especially in full shots, which you see more of here than in the first two “Alien” films.

For movement, the director referenced the leopard and jaguar. “Their body does all these contortions, but the head stays perfectly locked on its target, almost like its head is on a gimbal,” added Barba. “And that’s how you partially know that thing means business.

“But the second you get in a puppet, the head’s moving around and things aren’t quite the same, so Fede pushed Legacy to build gimbals into the mechanics of the heads, so they would have that same kind of motion. And the first test we saw was night and day between a guy in a suit with something on its head and a real creature because its head was now doing its own thing.”

When it came to CG, Barba found animating the Xeno one of the most challenging aspects of the movie. “There are a lot of subtleties that go along with how that creature moves. Again, it has to have its own body language so that it’s scary. Xenos don’t have eyes, so that was an important consideration. Does it recognize you? Does it not recognize you? Fede had all of these things that he felt strongly about.”

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The most complex set piece was an elevator fight in zero gravity, giving Cailee Spaeny’s Rain and her adopted brother Andy (David Jonsson) a fighting chance against the Xenos. ILM did the VFX (supervised by Nelson Sepulveda), which was aided visually by traditional backlighting.

“That was shot on two main sets: a vertical two-story and a horizontal five-story,” Barba said. “That way we could run our actors on wire rigs with our stunt team and fly them back and forth, up and down. And then it’s everything goes: We shot with our practical Xenos where we could, we shot with a mixture where we’re augmenting the practical Xenos we shot with set pieces and added CG Xenos to it. And there were certainly practical Facehuggers and CG Facehuggers in that sequence.”

The main Xeno they called Sparky, which was supported by multiple Xenos crawling up and was soon joined by supporting Facehuggers. Then, during the ensuing battle, Andy falls with the Xeno all the way down to the elevator floor. ILM also did the floating VFX to sell the zero gravity, kicking off with Rain’s CG gun floating off her back at the bottom of the elevator.

“There’s a section with a full-CG Rain where her hair and body are floating around in a couple places,” added Barba. “And then a mixture of real and CG Andy. As the scene came together editorially, we knew what we had to add. Things like the straps flopping around, just so the audience never gets the idea where up really is. And the zero-g acid and pieces and shells of the Xenos, so the audience understands what’s going on, knowing that if the acid hits the ground it leads to the depressurization of the station.

“So it was pretty much every technique there is, and when it all came together, it worked,” Barba said. “But every shot had its challenge because of either gravity going up or down, whether we could fit the practical Xenos into the set, or whether we could support the practical Xenos if they could move the way we needed them to. That’s really what dictated it.”