On the set of His Dark Materials, Dafne Keen is about to see a bear.


With battle raging around her, snowflakes flying and alarms ringing, the young actor – who plays lead character Lyra in the BBC’s new adaptation of Philip Pullman’s acclaimed novel – sprints down a corridor, dodging enemies and fighting for freedom.

And just when all seems lost, she looks up, seeing her saviour. A broad smile breaks out as she sees who’s standing above and ready to save her… a man wearing a white, faux-bearskin rug on his head.

OK, on set Pullman’s trademark armoured bears (or panserbjørn) aren’t much to look at – when they finally arrive on-screen, they’re an incredibly impressive achievement, realistic and filled with character, a triumph of puppetry and visual effects. If anything, they’re even more impressive than the animal dæmons that have appeared in every other episode so far.

But how were they brought to life? What did the actors film with on set, and what were the biggest challenges?

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Happily, after we’d suitably calmed down from all the excitement, the behind-the-scenes team were happy to fill us in…


While the 2007 movie adaptation of His Dark Materials (titled The Golden Compass) wasn’t exactly beloved by fans, it did win plaudits for its VFX, with the work of independent company Framestore winning the film its only Oscar.

Now, over a decade later, the new adaptation would have to surpass even that achievement – which is why Framestore were brought on board again to work on the TV series, marking them out as the only common element between both adaptations.

“Framestore did the original bears in the original film, which we won the Oscar for, and we're doing the bears again, now,” VFX supervisor Russell Dodgson told us.

“And what's really interesting about that is certain things we computationally couldn't do then, we can do now – but obviously it's harder work.”

And the digital work on the bears didn’t begin after the shoot had already concluded, as many might expect. In fact, before a single scene of the panserbjørn storyline had been committed to film on season one, Framestore and Bad Wolf’s in-house VFX gurus were working hard on previsualizations for the bears – in other words, plotting out scripted scenes in basic computer animation in specially-rendered environments, so they could work out how the bears would look before the directors started work.

“That was a combination of Framestore's bear animation and our [interactive set] environment,” VFX artist and pre-vis supervisor Dan May told RadioTimes.com. “We blocked out the sequence with Russell and the stunt guys downstairs.

“They animated the bears to quite a high level in pre-vis, that that pre-vis was then brought to our [digital] set with all its textures.”

Iorek Byrnison in His Dark Materials (BBC)

In other words, basic digital bears were added onto a specially-mapped digital set, blocking out the scene before anyone had even turned on a camera and creating a “virtual shoot.” And when it came to actually filming the sequence IRL, this preparation meant that the bears could (sort of) be on set as well, with specially-prepared screens and virtual “cameras” allowing the production team to check where the animated, moving bears were at all times.

“When they shot the sequence, they were able to bring that animation and the virtual camera angles, and see them live on set,” May explained.

“They were able to line up a digital bear with a real set. And that is not a first, because they're doing that sort of thing on Jungle Book and Avatar. But we're doing it on a more affordable, sustainable way.”

Though of course, it wasn’t just digital bears lurking on set…


As with the dæmons, the bears on set were built and puppeteered by Brian Fisher and his eight-person team, with various different rigs and outfits utilised by the team for different purposes.

“There's about seven to 10 different bear rigs,” VFX supervisor Dodgson told us.

“There's one for smashing into stuntmen, there's one for representing his face, there's one where there's literally a guy with a glove on putting it on his face.

For example, sometimes the bear was just represented by actor Joe Tandberg (who also provides Iorek’s voice onscreen) wearing (functionally) a bearskin costume, while other times he wore a special rig (pictured exclusively above) that allowed Iorek’s bear head to hang in front of his own.

Other times, he just wore a plain boiler suit with a light rig over his face, or stepped away in favour of a static model (pictured) to help the crew include Iorek’s scale, or was replaced by a large grey cushion for scenes where Iorek was less mobile or in a confined space.

“You're basically in a green room, with a weird grey thing which is supposed to be a bear, and with Lin singing? It's just all very weird,” Dafne Keen, who plays Lyra in the series, told us.

And of course, a lot of the time the full-time puppeteers took over. For example, while on set RadioTimes.com was shown a large puppet version of Iorek operated by two people to impressive effect. Within the rig, one puppeteer wears an ordinary large hiking backpack, leans forward to face the ground and hoists two long poles forward, with a mesh bear head that he can control and turn at the end of the poles.

Another man behind holds two strings to control the front legs. Together they can rear the bear to his full height, stalk him around an area and generally bring him to life.

Joe Tandberg on the set of His Dark Materials (BBC)

In His Dark Materials season one episode four, another bear head – one with Iorek’s snarling teeth – was used for a scene where he attacks a foe, and generally speaking the team tried hard to keep things simple instead of using complicated mechanical rigs or creations.

“When the bear attacks - that was much more stuntman, him, us throwing him around on a mat until we worked out something that we liked,” Dodgson says. “We take a very human, organic, what I call a man-tronic approach to things that you might take or do in a technical perspective.

“When he's getting dragged around by the bear it is just a guy in a boiler suit and [the victim’s] on a wire, and that's it.”

Riding Iorek

Dafne Keen riding the polar bear rig in His Dark Materials (BBC)

But the fighting wasn’t the only filming challenge. In fact, a key action shot that everyone was even more keen to get right comes later in season one, when Lyra rides on Iorek’s back as the pair travel into a dangerous new area.

On set, the human portion of the shot was achieved by creating a special rig for Dafne Keen to ride (pictured above) – but unlike similar ridable CGI animals like the dragons of Game of Thrones, it wasn’t mechanical, instead requiring the puppeteers to move it themselves.

“When Lyra's riding a bear, it's all operated by a human in a backpack,” Dodgson said. “You know, we don't bring in rigs and mechanically programme them because it's quite slow to do, and it means you get less takes at it.”

“To get the specifics, the biomechanics behind how a polar bear’s gait runs, we had to go through and, with the animators, actually break it down into segments, figure out how we can translate that into something that has movement and life but is not purely mechanical,” puppeteer Brian Fisher told us.

“The second you go into a mechanical movement, you can speed it up, you can slow it down, but it is always rhythmic, whereas we don’t work in binary movements.”

As you can see in the above video, RadioTimes.com actually got the chance to try out the bear rig while on set, and can confirm it’s definitely man-powered – and surprisingly bouncy.

“I loved the bear rig,” Keen herself us. “Though I was too light for it.

“It was very funny. They made this rig, and they didn't calculate my weight. So they had to then harness me, because I bounced too much off the bear. So that was really fun.”

“Although I felt kind of bad because I had two human beings bouncing up and down underneath me…”

The final touches

Obviously, the lion’s share of the work done by the VFX team comes after the filming as they gradually work on creating and animating CGI shots right up until broadcast. And for Dodgson and his team, no detail was too small when it came to the armoured bears.

“In our version of Iorek now he has the muscles underneath [his fur] that flex as he moves, and that also drives the fat on him to jiggle as he runs,” Dodgson told us.

“But then the skin actually slides over the bones and the ribs, which makes the fur that's attached to the skin slide over that as well. All of that together gives you something that feels really realistic.

“So again,” he concluded “the appetite and the ability is higher – therefore the workload is higher.”

Oh well - hopefully, the time and trouble wasn’t too unbear-able.

This article was originally published in November 2019


His Dark Materials airs on BBC One at 8.10pm on Sundays. Want something else to watch? Check out our TV Guide.