The VFX Supervisor of the Oscar-nominated Alien: Romulus has revealed how one impressive practical effects sequence had to be entirely recreated with CGI. Directed by Fede Álvarez, Alien: Romulus follows a group of young space colonists who encounter Xenomorphs, facehuggers, and some terrifying new creatures while scavenging an abandoned space station. One of its most nightmarish additions, the Offspring, was brought to life using real prosthetics and a full-body suit worn by Robert Bobroczkyi. The 2024 installment has since garnered an Oscar nomination for Best Visual Effects.

In an interview with ScreenRant‘s Grant Hermanns, VFX Supervisor Eric Barba explained the difficult decision to replace a practical sequence featuring the Offspring with CGI. The original scene captivated test audiences but had to be removed due to “editorial” restraints. Barba praised Bobroczkyi’s performance and the team’s practical work but credited Weta Workshop (The Lord of the Rings) for faithfully recreating the eerie moment with CGI. Here’s what he had to say:

Well, that was something that, even in the first test screening, we all sat in the back row and kind of watched to see how the audience responds. And there’s that moment when [the Offspring is] on all fours, the first time we see him, and the music dies down, and we look over, and we’re just all listening to hear how’s the audience reacting? When the audience is silenced, and you hear gasps, you’re like, “Alright, this is working.”

Because that’s how he felt on set with him. He was amazing, and there was a really fantastic sequence where he’s running down the hallway, and the cold gas is kind of coming behind him, and we just see silhouettes of him as he’s chasing Kay down the hallway. We had these great sH๏τs, these fragments of the silhouette with this giant creature, and it was so scary.

And it was in camera, and it looked amazing, but editorially, we couldn’t keep it because of some other things. So, one of Weta’s tasks was to recreate what we actually sH๏τ, because it was so beautiful, and they did a great job doing that. But there’s things that we got because we had [Bobroczkyi] there, and we could shoot with him, and the actors could react to him. You didn’t want to be too close to him, I mean, because he’s so otherworldly with his proportions.

And then, in that costume with the goop coming off him, he really was terrifying, and he played to it. He was great.

What Alien: Romulus’ Offspring CGI Recreation Means

The Practical Effects & CGI Behind Its Lifelike Horror

The decision to replace a practical sH๏τ of the Offspring with CGI reveals the complex interplay between practical and digital effects in Alien: Romulus. While the film relied heavily on practical techniques to create its terrifying creatures (such as its iconic chest-bursting scene), the sequence demonstrates that CGI remains a useful tool for refining and enhancing scenes when necessary. The Offspring was largely practical, with a full-body suit that gave the actors a tangible, terrifying presence to react to once one of the colonists gave birth to the human-xenomorph hybrid.

This balance between practical and digital effects is an illuminating peak in Alien: Romulus‘ most memorable horror creation. Bobroczkyi’s intricate prosthetics, created by Legacy Effects (Avatar, The Avengers), added a disturbing realism to the Offspring. CGI enhancements helped refine his final appearance as the creature’s tail and minor facial adjustments were added in post-production. Much like how James Cameron’s award-winning sequel and Ridley Scott’s original Alien used a combination of practical puppetry and subtle visual tricks, Alien: Romulus utilizes CGI selectively to amplify the horror without overshadowing the practical craftsmanship.

Our Take On Alien: Romulus’ Practical & CGI Effects

A Hybrid Approach That Still Honors The Franchise

While it’s unfortunate that a stunning practical sequence didn’t make the final cut, Alien: Romulus still shows how practical effects remain essential to the franchise’s nightmarish horror. By using CGI as a tool rather than a crutch, the Offspring was still allowed to feel as menacing and real as possible for the actors on set and the audiences in the theater. With Alien: Earth on the horizon, it will be interesting to see if the upcoming FX series continues this tradition, preserving the franchise’s legacy of using (mostly) practical effects behind its most unforgettable horror moments.