From Code to Curse: How Specialized Rigging Systems Delivered the Defining Visual Effects of Weapons

Few horror films have made as big a cultural impact in recent years as Zach Cregger’s Weapons. Released in 2025 and following up the filmmaker’s searing entry into the genre with Barbarian a few years prior, Weapons not only went on to become a box office phenomenon in its own right, but also earned immense critical praise. This even included an Academy Award for Amy Madigan for her performance as the film’s antagonist, something that has happened only a handful of times in the horror genre throughout the ceremony’s history.

Audiences, critics, and fellow filmmakers were very much in agreement that Weapons was a remarkable achievement of craft, and Zhehao Qiao was an essential part of that with his visual effects work.

Inside Qiao’s Work on Weapons

As the Lead Rigger on Weapons, Qiao was tasked not only with wielding substantial granular technical insight but also with applying it in creative, boundary-pushing ways. It was decided early in the film’s development that, as characters underwent supernatural transformations throughout the story, those physical changes would be created using digital doubles.

This approach had many benefits that on-set practical effects wouldn’t have allowed, but it also brought its own substantial obstacles. Each of these characters was set to perform high-stakes physical actions that threatened to push the boundaries of character rigging in palpable ways. Fortunately, Qiao and his team proved more than up to the task.

Qiao’s primary work on Weapons wound up proving essential to three central sequences: the “cursed” digital face replacements, a robust full-body double for the character Marcus, and a complex, specialized skin-peeling effect.

Managing a Creative Team

In addition to his hands-on work as Lead Rigger, Qiao also served as the team leader for an entire group within the rigging team. Here, his role was to ensure that he and the team not only completed their work within the allotted time but also brought it as close as possible to director Zach Cregger’s vision. Qiao’s overall philosophy for managing the rigging team on such a unique and demanding project was to protect the team’s energy and maximize their focus on quality.

A substantial amount of the team’s time was spent creating similar digital double setups. Generally, doing this kind of repetitive work could easily lead to disengagement among the artists, but Qiao took active measures to prevent it, and it made all the difference. His strategy was to automate mechanical, repetitive tasks by turning them into custom tools and scripts, thus allowing artists to focus their time and energy on the creative details that truly mattered, such as refining subtle facial deformations around the enlarged eyes or ensuring the overall believability of a performance.

Qiao also nurtured a strong sense of responsibility by ensuring that the same artist maintained ownership of a character from start to finish, consistently resulting in higher-quality work. This focus on tool development proved to be the project’s most significant lesson, with Qiao reducing a week of manual work to a single day by modifying an auto-facial rigging system.

Digital Doubles

The successful delivery of the digital doubles required a constant, iterative collaboration with the modeling and animation departments. With modelers, the process began by integrating initial sculpts, which often revealed issues such as eyelids collapsing into the enlarged eyeballs once the rigs were put in motion.

Qiao’s team provided clear notes to modelers and added extra rigging layers to support the modified shapes, drawing on his experience to provide early guidance and flag high-risk expressions before the assets moved down the pipeline. With animators, the collaboration was a continuous feedback loop. Qiao’s team would adapt the rig by adding new ‘tweaker’ controls, allowing animators to fine-tune micro-movements and ensure the digital face faithfully translated the actor’s original performance.

Facial Reconfiguration

The film’s central visual effect, characters with enlarged and protruding eyes, required full digital face replacements and was the source of the most significant technical hurdle. Because the eyes were so large, the surrounding geometry and eyelids were severely compressed, leading to frequent intersections and unnatural deformations, especially when multiple expressions were combined.

To solve this, the team developed rig-side solutions that went beyond simple modeling fixes by incorporating intermediate shapes and combination corrections that activated only at specific values (e.g., 50% of a blink) or when two expressions were active simultaneously.

In addition to the facial work, Qiao oversaw two other demanding technical assets. The full-body rig for the character Marcus, built on the team’s component-based auto-rigging system, needed to withstand extreme, non-anatomical joint angles in sequences such as violent strikes and throws.

While it was a simpler biped rig than the facial replacements, it required significant, detailed, character-specific corrective work to ensure muscles visibly tensed and bulged under strain and that the deformation held up under the character’s larger size and the extreme poses required by the animation.

Finally, for the complex scene in which a character’s facial skin is peeled away, Qiao repurposed an existing tentacle-and-tail system, treating the skin as a flexible object attached to an invisible path to create a smooth, organic peel.

Importantly, he added a second, custom rigging layer at the tip of the peeled skin, enabling it to curl tightly in a disturbing manner, something the original system couldn’t do on its own. To maintain realism, Qiao incorporated limits into the rig controls to prevent the skin from stretching excessively and breaking the illusion.

Looking Back, Moving Forward

Looking back at Weapons, Qiao is most proud of the eye effects, which validated the strength of their auto facial rigging system and required constant custom work and communication with other departments. Seeing the final result and the audience reaction confirmed that the technical innovation successfully contributed to one of the film’s most memorable visual effects.