Behind Koala FX’s visual effects for this latest survival-thriller.
Following the vertiginous success of Fall, the sequel Fall 2: Deadpoint takes its survival-thriller premise from a single isolated tower and expands it into an entire mountain environment. Directed by the Spierig brothers, Michael and Peter Spierig, from a screenplay by Scott Mann and Jonathan Frank, the film follows Jax Hunter (Harriet Slater), who, still grieving the death of her sister Shiloh, joins Shiloh’s friend Luce (Arsema Thomas) on a climb of Thailand’s treacherous Mount Kwan.
Their memorial hike takes a disastrous turn when a rockslide leaves the pair stranded thousands of feet above the ground on a narrow, precarious plank walk, forcing them to navigate an increasingly dangerous route back down the mountain while battling exposure, exhaustion and sheer vertigo.
The production required extensive visual effects to create the scale and geography of the mountainous areas in the film. The plank structures were physically constructed on a quarry wall in Thailand, with sections positioned around six metres above the ground for practical filming and stunt work, before VFX extended the rock walls and surrounding landscapes.
Koala FX ultimately delivered more than 400 VFX shots, creating a full CG representation of Mount Kwan and combining digital matte painting, 2.5D set extensions and CG environments. The work included building and maintaining the continuity of the mountain across changing weather and lighting conditions.
befores & afters caught up with Koala FX managing director and co-founder Dasha Sherman, and Koala FX creative director and visual effects supervisor Menelaos Pampoukidis, to find out more.
From TV tower to mountain
Koala FX had previously crafted visual effects for Fall, where the two main characters were stuck for most of the film at the top of a TV tower they had climbed. The sequel, being set on a Thai mountain, instantly brought with it a set of brand new challenges. “The difference between Fall and Fall 2,” shares Sherman, “is that you’ve got one point for Fall with a 360 of the horizon around it. But on Fall 2, we had all the rock formations. It’s much less straightforward. It’s a completely different beast for us because it has left and right, it has up and down, in comparison to that one point.”
“It just became more complex to have to align all these convolutions of the rocks,” adds Pampoukidis. “You want to find some sub-edges that allow you to do seamless roto. Any small bump that is not aligned with your CG model will feel like it’s floating a little bit in this area. So, it becomes actually extremely more complex than a single pole.”
Production established a range of mountain wall sections at the Thailand quarry to film climbing and plank-walking sequences, as well as the final precarious bridge crossing. The intention here, of course, was to shoot outdoors in natural light so that the final visual effects shots would look as realistic as possible. Some bluescreens were able to be used during filming, although in general they were not expansive. “If I could, I would have had a few more bluescreens,” admits Pampoukidis. “However, it was not always in our control because the film is not a VFX movie, right? The actor performance and the camera work were really important. To really put up a huge bluescreen behind them for every set-up would have needed cherry pickers there and one or two hours to move them each time.”
“In 2026, roto tools are really good, and people are really good at roto, so it wasn’t a huge deal to do all this roto perfectly and seamlessly,” continues Pampoukidis. “What we did, though, and it was really important, was that we always matched the lighting. When you have a bluescreen, all these edges are important, and you can maintain them in a flat way, and that’s really why you truly need it. And then if you want to over-expose something which is brighter or darker, you can shift the edges, whereas with roto, it’s much harder to do that because you need to reconstruct these edges. So what we did was always maintain the lighting scenario. We very rarely changed it and this allowed us to pretty much maintain all the edges as they were.”
The world of Fall 2
The environments depicted in the film included both ‘close-up’ extensions of the rock wall, and wider shots of the fictional Mount Kwan and its surrounds. “The mountain itself is one of the cast,” states Sherman. “It’s one of the protagonists, really. “It has its own character. It has to be scary at points. It has to be friendly at points. It has to actually interact with them, so it creates some obstacles which they have to overcome. So, it was a little bit like a magical creature for us.”
LiDAR scans and textures formed part of the environment builds for the rocky formations, and were part of aiding camera alignments for extensions. Pampoukidis notes, however, that so much of the environment work related to close-ups. “We actually had different levels of detail or LODs. An asset can look great from afar, then you need another asset to look great closer up, and another asset to look good extremely close. We had to create very detailed CG assets for the closer levels. Further away, we could use the LiDAR and then coat it on top with better textures, and it worked well. But when you go closer, we had to re-create it with CG.”
The Koala FX team utilized a trick to aid in dealing with close-up CG rocks, shares Pampoukidis. “If you take a rock and you zoom in, it can look like a huge rock, so we could use really small rocks, but then bring them closer, and the texture was looking good, as long as there was no tiling. So, when you zoom in, it’s the same rock, but smaller, and you smooth and wear its edges. That’s how we were able to keep the high LOD when you go close to it.”
Where AI and machine learning comes in
On the first Fall film, Scott Mann’s Flawless used its AI tool TrueSync to redub some scenes where a few F-bombs needed to be changed for the film’s classification. The Koala FX team had closely witnessed the implementation of that tool, and Flawless’ continued development, all while the age of AI and machine learning in visual effects has quickly risen in recent years.
“We are very integrated with Flawless and what they’ve been doing,” says Sherman. “We’ve become almost a testing platform for them. On Fall 2, it was more like an R&D process. What we were working on in particular was quite a lot of wire removals. They’re usually considered the easy part, but they were right across the whole film, over hundreds of shots. Flawless would be trying to perfect the tool and we would be giving them feedback.”
The benefit here, suggests Pampoukidis, was that Koala FX’s experience in visual effects production and visual effects pipelines meant that the development of any AI tools could be stress-tested in real-world situations. Areas that VFX artists are already used to dealing with, such as light flicker on plates, de-graining before working on the VFX, or getting a shot to a certain level with a particular tool and then spot-fixing any areas for a final polish, were some of the ‘hands-on’ pieces of advice they could offer to those developing AI tools—“A lot of times I’ve seen people who develop AI tools struggle sometimes to perfect something that we have mastered in the VFX world,” says Pampoukidis, noting that visual effects artists are well placed to be front and center with new AI tool developments.
Sherman further indicates that the relationship with Flawless is set to continue on Fall 3 (now in production with Scott Mann directing), especially since that film will also be a survival-thriller, with plenty of opportunities for wire removals and the like.
Here at befores & afters, we can’t wait to see what escalating high-rise situations the characters might get into next, and what the visual effects and AI/ML solutions will be.
