By Karen Moltenbrey

Zombies used to have a short life span, awakening sometime during October, just in time for Halloween, before once again stumbling back into obscurity for another year. But thanks to the hit series The Walking Dead and its spin-off Fear the Walking Dead, the popularity of these monsters is infectious, turning them — and the shows — into cult phenomenon.

The Walking Dead’s rise in popularity started almost immediately with the series’ US debut, on October 31, 2010, on AMC. The storyline began when Rick Grimes, a sheriff deputy, awakens from a coma to find the world overrun by zombies. He and other survivors in the Atlanta area then band together to fight off these so-called “walkers,” as well as other tribes of survivors intent on ensuring their own survival in this post-apocalyptic world, no matter the cost.

In mid-2015, the show gave rise to the companion series Fear the Walking Dead. Fear, a prequel to The Walking Dead, takes place at the start of the zombie apocalypse and follows a different set of characters as they struggle to survive on the West Coast.

And the series’ visual effects are, well, to die for. Literally.

Burbank’s Picture Shop began creating the effects for Walk starting last season and is now in the midst of Season 9 (The studio splits the lion’s share of the work on the show with Goodbye Kansas Studios). Picture Shop provides visual effects for Fear, as well (Season 4, Episodes 1 through 8).

According to Christian Cardona, senior visual effects supervisor at Picture Shop, the crux of the work for both series includes character “kill” effects and environment augmentations. “We do a lot of what we call ‘walker kills.’ What that usually requires is weapon extensions, whereby the weapon gets inserted into the walkers, and then the ensuing wounds. We have to track the wounds onto the practical walkers and then also do blood sims during those kills,” he explains. “That accounts for probably 50 to 60 percent of the work.”

The only way to kill a walker is to damage its brain or destroy its body. Therefore, each episode contains its fair share of bodily damage to the zombies (and, sometimes, to the humans trying to keep them and the adversarial tribes at bay).

Cardona notes that it took the group a few episodes to nail down the blood aesthetic the producers were looking for — the look of the blood as well as how it should flow from a walker’s mouth. “Throughout the season, we’ve definitely zeroed in on that and have really gotten a good system down, where now it takes us just a fraction of the time,” he says.

Nevertheless, the work has to be exact. “The client wants everything to be photoreal; they don’t want it to look like anything was added. With that said, they scrutinize every shot, frame by frame and pixel by pixel, so we definitely have to do our due diligence and make sure our work adheres to their standard,” Cardona says. “And they will art direct every drop of blood. They know what they want, and we make sure we deliver that.”

The Walking Dead

There is indeed consistency in the overall look of the blood and wounds, as well as the walkers themselves in each of the shows, although there was one scene in Walk whereby the walkers were stuck in a toxic sludge. As a result, their skin was more pale and saggy. “It was a unique scenario where we could change their appearance and the look of the blood for that episode to illustrate that these walkers were different,” recalls Cardona.

The Walking Dead
In Walk, the majority of the hero walkers — either individuals or those in small groups – are actors with prosthetic makeup, or in some cases, practical models. But when there are more than two dozen or so walkers in a shot, they are CG creations.

Whether a practical or digital walker is used for the show often depends on the action in the scene. Walker kills are prevalent throughout the series, as it is in Fear, and often this involves a decapitation or a scalping, “because in order to kill the walkers, they have to be either shot in the head or stabbed,” Cardona points out. “Oftentimes when that happens, we have to cut from the person with the makeup and prosthetics and replace the entire head digitally before chopping it off for the scene.”

Season 8 Episode 14 featured a practical walker with a broken body strapped to a dolly cart, its head locked in position on the cart. As a form of torture, the cart was wheeled close enough for the walker to bite a victim. Initially, the walker was practical, but Picture Shop artists ended up replacing it with a CG model.

“The client wasn’t really happy with the practical version on set. It looked rubbery, like an animatronic walker, which it was. It needed to be fleshier, a little more real,” says Cardona. “The blood and wounds felt too dry, and the muscles had to contract.”

Fear the Walking Dead

In fact, Cardona describes that sequence as one of the more challenging from Season 8. “It was close to the camera and had to be photoreal. It wasn’t just one shot, either; there were over a dozen shots in the scene, with multiple angles and long takes.”

The team used the practical cart walker’s head in the shots but replaced the body and arms, which also had been locked to the cart, requiring intricate match-moving. “We had to be spot on and tight, so there was a lot of soft tracking as well, since the camera was moving everywhere,” recalls Cardona. “And then we had to get that walker to look photoreal.”

Compounding this scene even more was the fact that the main character shoots the cart walker, requiring the addition of bullet hits and resulting wounds.

Zombie Nation
For the upcoming Season 9 (premiering October 7), Picture Shop began using a new system for generating large crowds of walkers. According to Cardona, the animators introduced Golaem’s population tool into the pipeline to help with the mass crowd simulations for the walker herds that will appear during the season. Previously, the artists used the particle system in Autodesk’s Maya for this task, “but we needed something that was more robust, something created specifically to do this kind of effect, especially on a TV schedule and with a TV pipeline and workflow,” he adds.

During this past off-season, the artists began establishing a system that would source the walker assets the group had created for Season 8 and in the off-season to prepare for Season 9. “We were modeling walkers and using some of the walkers from Season 8, and standardizing them all with the same T-pose so we could easily swap out rigs and customize and create a lot of variations with textures, changing their clothes, skin color and hair,” explains Cardona. “So when we have to create walker herds, we can easily get five or six variations from a single walker. We end up with a lot of variations in our herd sims without having to create a brand-new walker every time.”

And make no mistake, there will be more herds of walkers in Season 9 than viewers have seen in previous seasons.

The Walking Dead

Other VFX
On average, Picture Shop created 40 to 50 VFX shots per episode during Season 8 of The Walking Dead, with a typical turnaround time of two to three weeks. In addition to the kills and their associated effects, the group also built set extensions. For instance, most of Season 8 (and 7) revolved around what is called “the Sanctuary,” an old factory that is now home to The Saviors, with whom Grimes and his group must interact. The first two floors were practically built, and then Picture Shop extended the structure digitally by another 12 stories. At one point, a gun fight ensues, which called for the CG artists to break out all the windows — another visual effect.

“The group didn’t move far from their location in Season 8, so the need for additional set extensions wasn’t as high as it had been in earlier seasons,” adds Cardona.

Episode 8 of Walk — which has the tribes fighting each other more so than the walkers — did start off with a bang, however. In the first episode of the season, Daryl, Grimes’ trusted lieutenant, shoots a box of explosives, ripping a CG walker in half — work that Cardona describes as “challenging.” In another shot, an RPG blows up another tribe member; in it, the actor had to be swapped out for a digital double that had been projection modeled.

Cardona has seen an evolution in the effects Picture Shop is providing for Walk in particular. Some of the more interesting effects will be coming in Season 9, he teases. “We’ve been working on some of the stuff over the summer and have spent time in R&D on one effect in particular — something new that the audience hasn’t seen before,” he says.

In the upcoming season, nature is taking over, and there will be overgrown vegetation on all the buildings and structures. “With that said, we are doing an effect whereby we take a murder of crows and have them swarm similar to the murmuration of starlings, which wheel and dart through the sky in tight, fluid formations,” says Cardona. “This is something you will see through the course of the season.”

The Walking Dead

For this work, the artists built and rigged a crow in Maya and generated various animation cycles, which were cached out and used as a particle simulation within Side Effects’ Houdini.

While creating this effect was not nearly as time-consuming as setting up the crowd simulation in Golaem, “it was something unique, and we had to figure out an approach that gave us the flexibility to art direct and change [the results] quickly,” Cardona notes. “And, it’s an effect that has nothing to do with walkers, but it tells a big part of the story of what is happening to the world around them.”

In terms of the other overall effects in Walk and Fear, the Picture Shop artists use primarily Autodesk’s 3ds Max, although Maya is also used, albeit mainly for the Golaem crowd work. Yet once the sim is complete, the artists cache the results and bake out all the animation within Maya, then export it into Max. Rendering is done in Chaos’ V-Ray for 3ds Max.

In addition, the artists use Pixologic’s ZBrush for a lot of the organic modeling, mostly for the walkers. For effects, the crew usually turns to Houdini.

The effects that Picture Shop delivers for The Walking Dead are unique — in terms of the blood and gore — from other shows the studio works on, such as Hawaii Five-0 and MacGyver, which call for more traditional VFX, like muzzle flashes and explosions, as well as set extensions. “It’s more hard-surface modeling stuff, whereas Walk, for the most part, is a lot more organic,” Cardona adds. “And the tone is completely different, obviously.”

Monster Mash
Picture Shop performs the same type of work for Fear as it does for Walk — mostly weapon extensions and walker kills. Cardona notes there is a cohesiveness in the effects between the two shows, especially now that the timeline of both stories is nearly the same. Fear started at the beginning of the apocalypse, when the walkers were “fresher, and the blood kills were a little bigger, because the thinking was that there would be more blood present in the walkers at that point,” he explains.

Insofar as the general walker kills are concerned, the actors never really make a physical impact with their stabbing motions, so oftentimes their hands are not in the right positions or the reaction time of the walker is off. In these instances, it is up to the VFX artists to digitally rectify the action and reaction — for instance, separating and repositioning the actor’s arm, stabilizing it, then tracking on the weapon that is placed in their hand, as well as stabilizing the walker, adding the wound, and then adding the weapon extension. This holds true for both series.

“Sometimes this can be challenging because the camera is also moving, so it requires significant roto work, and we have to deconstruct the shot and reconstruct it back again,” says Cardona. “There are plenty of these types of shots we have to do for both Walk and Fear.”

For the tracking on this and other work, the studio uses Andersson Technologies’ SynthEyes; for the planar tracking, Boris FX’s Mocha, formerly from Imagineer Systems.

According to Cardona, the overall look of the walkers has changed throughout the course of the Fear seasons. In Walk, they are more decayed, whereas in Fear, they still look like humans for the most part, not as skeletal. But, that has now changed, and with a more cohesive look between the walkers is a more cohesive look with some of the VFX, particularly the blood effects going forward.

However, there is one big difference between the two shows. Walk is still shot on film, 16mm, while Fear is shot digitally, so the graininess is quite heavy with Walk. “It affects our tracking because there is so much noise. Often we would de-grain [the footage] to do the tracking, and then add the grain back in. Also, any time we have a bluescreen shot where we have to pull keys, it’s a problem,” says Cardona.

Indeed, honing the effects on The Walking Dead gives the artists a leg up when it comes to Fear. Another advantage: Picture Shop performs the color and finishing for both shows, as well, which can result in some emergency VFX work for the crew, especially during a time crunch. In fact, the colorists at the facility created the custom 16mm grain pattern that the artists use now during the tracking process. It was generated by the colorists when the client was considering migrating Walk to digital format but then decided to retain the current structure.

Another plus: The Walking Dead executives are also located in the same building as Picture Shop, several floors up. “They just moved here, and it’s convenient for everyone. We can do spot sessions with VFX producer Jason Sax or showrunner Angela Kang (who recently took over that role from Scott Gimple).”

At Comic-Con San Diego a few weeks ago, the series was a fan favorite, and online there is talk about plans for upcoming seasons. So, it appears these walkers still have a lot of life left in them, if fans — and the digital artists — have their way.

Karen Moltenbrey is a longtime writer and editor in the CG and post industries.