A Monster Calls : MPC’s Character work

MPC developed complex facial and character tools to bring a monster to life for ‘A Monster Calls’.

12-year-old Conor is dealing with far more than other boys his age. His beloved and devoted mother (Felicity Jones) is ill. He has little in common with his imperious grandmother. His father has resettled thousands of miles away. But Conor finds a most unlikely ally when the Monster appears at his bedroom window one night.



 MPC Montreal VFX Supervisor Ferran Domenech led MPC’s team, however the MPC’s Modelling and Assets team was in London. MPC completing more than 180 shots, to deliver the touching vision of director Juan Antonio Bayona.



The face of a monster

Audiomotion did the capture

MPC’s team was presented with the challenge of creating the titular Monster (voiced by Liam Neeson) for the transformation and close-ups shots throughout the movie.  MPC handled the talking performance shots as well as the modeling of the creature’s full body, sharing the finished asset with other vendors, overseen by Production VFX Supervisor Felix Berge.

Liam Neeson and Director J. A. Bayona spent two weeks on set at Europe’s large motion capture facility in Oxford. The Audiomotion team worked with storyboards, artwork, 3D models and previs to help create the scenes, allowing Bayona to conceptualise and recreate shots in the 3D scene via a virtual camera.


MPC Montreal’s work consisted mainly of close-up dialogue scenes of the monster against the emotional performances of young Conor O’Malley (Lewis MacDougall) throughout the film.  MPC’s team also created the transformation from a Yew tree into the monster and the enraged variation where he turns into a bigger and scarier version of himself with an internal fiery glow and protruding spiky branches.



MPC modelled and adjusted the monster’s facial anatomy from the original head scan supplied from production, to work for the expressive dialogue performances needed. The CG modelling team modelled and textured the whole body as a mix of different types of virtual wood pieces intertwined with branches and vines that were then rigged to articulate and simulate a musculature and nervous system.

Great attention was placed in the creation of the Monster’s eyes, which would be crucial in communicating emotion to the audience and are seen in extreme close-ups throughout the movie. They were re-designed to be closer to human eyes to achieve a deeper emotional connection with viewers whilst keeping a natural tree like base quality at its root. This was achieved by using textures from lighter wooden surfaces on the sclera, while the colour palette of the iris was derived from the moss that covers its body and the wet areas of the eyes based on different types of tree sap. The team started from a very accurate high resolution human eye model and deviated as necessary.

A face closeup (blowup)

The Monster’s facial rig required the most research and development as it had to be flexible enough to perform a wide range of expressions and lipsync dialogue whilst keeping to the structure of rigid pieces of wood.  For this, the whole face and body was built as a jigsaw of hundreds of sliding pieces that would neither stretch nor deform like rubber, but instead slide alongside each other. This approach was technically complex, but kept the movement of the face grounded in reality.

Blowup of the face detail

MPC’s Animation department stepped up to the challenge of animating emotional close-up performances for the monster as full keyframe animated shots; both for body and facial acting.  This was realised with a wide selection of directed video references of Liam Neeson for each scene. Although no motion capture data was used in the finals shots, the witness and helmet camera video from these sessions provided perfect guidance for the animators as they worked with the audio. This approach is best exemplified in the final emotional scenes as the monster helps Conor face his personal nightmare, delivering subtle true to life acting and facial performance.

Fxguide spoke to MPC Head of Modelling Chris Uyede (CU) and Lead Rigging TD David Gower (DG):

FXG: As the face has such a non-bending untraditional way of forming expressions – was it still a blendshape rig or was it much more a joint rig?

DG: It was actually a combination of both plus our in house deformers. The face was made up of individual plates which each had their own dynamics values to control secondary motion. We went in and individually tuned each area of the face by hand to achieve the best result. However, the broad motion was provided by a standard blendshape face rig.

headFXG: Did you scan the physical prop head, which was enormous?

CU: We worked off of a lidar scan of the practical head of the monster they constructed on set.

FXG: Can you discuss the lips and how you achieved various visemes? Were you after making lip shapes that matched at all to Liam’s mouth… I can see advantages of doing this for good lip sync – but of course there is no ‘plot’ reason to do this.

CU:  While the animated performance targeted Liam’s work on set, we built a custom set of FACS shapes adapt to the very different facial structure of our monster. There was a lot of iteration between blendshape modelling, rigging and animation to get solid emotive possibility.

FXG: How much did you break from the current methods of facial pipelines ie. the general pipeline of observing the actor in a range of FACS poses, it then fitting a rig and retargeting?

CU: We approached the facial work in a lot of the same way we normally would on a designed character, with the exception of its flexibility and texture as it is made of wood. It had to be flexible enough to perform a wide range of expressions and lipsync dialogue whilst keeping to the structure of rigid pieces of wood.

FXG: What did you rig the face in? Was it Maya?

DG: Yes, just Maya. Maya is the predominant piece of software we use for rigging. However, over many years, MPC have developed their own custom tools to extend the functionality of vanilla Maya which allows us to create rigs like The Monster. We based all of this around MPC’S facial rigging tech in the same way we’d approach a digital human, with the material and displacement being the primary differences.

FXG:Who’s idea was the particular texture palette?

CU: This came about as a collaboration between the texture artist, vfx supervisor and director. There were multiple versions selected and tried out before we arrived at it.

FXG: What resolution were the textures developed at?

CU: The textures were done at 8K

FXG: Did you experiment much with lower eye moisture, and tear wetness – this seems to be an interesting balance between tree eyes and human eyes?

CU: Yes that’s also correct. To get the balance between the two was a difficult thing to achieve but we were really happy with the final look.

FXG: Can you discuss this on set version in terms of the source of the design – was it solved and handed to you, or did the on set real head come from MPC design files? Clearly, the real and digital would match perfectly – in a perfect world…

CU: The on set head was used as reference and source material that we elaborated on, and in turn was based on conceptual 3d artwork.

A Monster’s World

MPC also worked on environments for Conor’s neighbourhood and the rooftop of his house as he and the monster converse in the middle of the night about the meaning of the stories they shared.



Set extensions for the final nightmare cemetery sequence were created by MPC’s team. For the action shots, MPC’s FX and Technical Animation departments created  destruction elements that collapse when the monster beats the earth with his fists, as well as other destroyable props when it rampages through the school cafeteria destroying tables, chairs, ground and the ceiling.



The Technical Animation department also took on the challenge of adding wind simulations to the small branches which sprout from the monster and added dynamic leaves and bark that would fall when the monster transformed from normal Yew tree into the 40 ft tall monster. For these transformations, MPC created a fully realised Yew tree with dynamic branches and leaves with a trunk that could be animated to break into pieces to reveal the monster hidden inside as he rips himself free of the canopy.

 Also you might like to check out our review of the effects in our vfxshow podcast.