When the gorgeous Planet Earth II premiered in the UK in November, one clip in particular turned heads. As it begins, a baby iguana, newly hatched from an egg buried in sand, tentatively pokes its head out above the surface — and then launches itself into one of the most thrilling chase sequences ever to grace television, courtesy of the iguana’s desire to live and a truly terrifying army of snakes.

The drama of “Snake Island” — as the Vox Culture team calls it — would not be denied. The clip raced around the internet quicker than the baby iguana fleeing certain peril, proving the power of combining life-and-death stakes with keen filmmaking and a tight edit.

To get more insight into the making of Planet Earth II, and the “Snake Island” sequence in particular, I spoke with series executive producer Mike Gunton and director Elizabeth White. The short version? Nature is pretty thrilling (and unforgiving) all on its own, but they’ve honed some techniques to better capture it anyway.

The following interview has been lightly edited and condensed for clarity.

Caroline Framke

So many of Planet Earth II’s scenes are shot and edited like sequences from an action movie. When you were filming, were you looking for that specific type of footage?

Mike Gunton

Obviously you have to work hard, and there’s a lot of craft in it, but actually, there’s so much natural drama in these things that they do drive ... they cry out to be presented in that way. You’re not turning a mundane piece of nothingness into something. They’re there.

The skill is in picking the best moments and making it work technically. Unfortunately, animals don’t hit their marks or read scripts or [respond to], “Action!” So a lot of it is what you manage to capture, but we always go with very clear ideas about the sorts of stories we want to tell and the parameters with which that story should be told. So we’re putting cameras in positions where we’ll get those sorts of images. Sometimes on this series we’ve actually had two cameras on one location, and that massively improves or helps your flexibility. ... It’s almost like a studio shoot, where you can go, “Okay, cut to camera one!” That has helped.

I think also the style that we’ve used with Planet Earth II, it’s very fluid, very dynamic camerawork. We’ve taken the camera off the tripod through these miniaturizations of gyro-stabilized mounts. We did a bit of that on some of our previous series, but now you almost think to yourself, “How the hell did we do anything in the past without these cameras?” Because now actually every shot is done like this.

Caroline Framke

So for a scene like the one my co-workers and I have dubbed “Snake Island” — our favorite movie of the year — I’d love to hear more about how something like that was shot. Was it as dramatic when you were shooting it as it became after editing? It sounds like most of these scenarios are.

Elizabeth White

Oh, yeah, a massive adrenaline rush. My worst ever role as director, because I spent most of the time covering my eyes going, “Did it get away?!”

The whole sequence is actually like eight minutes long, and we do show some [iguanas] that get away and some that don’t. Also, we very much have tried to mention in it that for the snakes, this is a brutal place to live. For the snakes, it’s their only really big feeding opportunity of the year.

So for that sequence, we wanted to tell that whole story. A nest of iguanas is — between four and six come out at any time, and so you do see successful ones and you do see ones that fail.

Mike Gunton

It’s not all carnage.

Elizabeth White

No, it’s not all carnage. [But] it is pretty brutal, and I think the big challenge on that sequence was that we obviously need to show the drama, because it’s obviously a massive adrenaline rush to be there and to film it, because you don’t know where those little iguanas are going to come up.

It starts with a hatchling pulling its head out of the sand, and that’s its opening moments of life. And we’re standing at the top of the beach with a pair of binoculars seeing this tiny little head, and it’s looking around and kind of going, “Oh, shit.”

Mike Gunton

And we know it’s “Oh, shit” more than he even does!

Elizabeth White

It’s really interesting with the iguanas. Some of them are really cocky, and they just kind of come out, and the little things just walk down the beach like, “Isn’t this really nice? We’re having such a nice day.” And one of the first we actually watched properly emerge — and in fact, the first we saw that revealed to us where we wanted to film the story — he properly freaked out and ran toward the rocks. And of course the problem is that then the snakes see them.

So as it kind of slowed down and panicked, running at the rocks, this sort of Medusa’s head of snakes came out of the wall.

We’d been there a couple of days at that point, and we’d been all around this whole peninsula looking for where we were going to get hatchlings. We were looking for hawks and frigate birds as well as snakes; we were looking for all the different things that prey on hatchlings. And then when we saw that, we called it “the Wall of Death.”

You have to be quite careful — you can’t walk across the beach because of hatchlings. We were working with a ranger who tells us where we can and can’t go. So we walked down to that wall, and literally a single crack had between eight and 12 snakes in it. That density of snakes [is] why we started to focus on that area of the beach. All the iguanas coming from that sand had to pass that way to get down to the colony, and the snakes know that. They’re smart. They’re there, homed in, watching the beach. That’s how we managed to get that amazing footage.

And it’s not pack hunting. Those snakes are absolutely each and every one out for itself.

Caroline Framke

Huh! That’s interesting, because it really looks like the snakes are teaming up to cut the iguana off.

Elizabeth White

Yeah, no. And you really notice that when one of them does catch it, they’re just ambushing. Some of them are in the wall — they’re higher up, they’ve got a better view of the beach — and the other ones are tucked down behind rocks and very much lying in ambush. But if one of them sees a movement and moves, that’s when they all kind of go, [gasp!].

Mike Gunton

That’s why you get that very sinister sense that they’re all in it together, but in fact, they’re all watching each other to see if anyone picks up first. [Elizabeth has] a theory that when they start, what the snakes are doing is getting into it, so when they first emerge, probably more [iguanas] get away then. But then the snakes start to clock that the iguanas are coming, they start to get homed in on it. So when you were there, it was all craziness.

The other thing to remember, of course, is that we shoot this in slow motion. So that whole event, when you were there —

Elizabeth White

It happened so quickly.

Mike Gunton

If you didn’t [shoot it in slow motion], you wouldn’t see anything. It would just be impossible to enjoy, but also you wouldn’t get the revelation. Slow motion allows you to see all the different strategies.

Elizabeth White

And some things you don’t see at the time. There’s one particular shot ... the snake actually comes and tries to bite the little one, and its face hits the rock and it gets pushed backward. You would’ve never seen that happen at the time. It’s only because we shot off speed, and then you look at it in slow motion through this lens and you’re like, “Wow.” That snake so nearly got that iguana and hit the rock instead.

Mike Gunton

That’s why the photographers are so extraordinary. They’re having to go almost with instinct. You can’t really make conscious decisions about what you’re doing.

Elizabeth White

There were two cameras [filming the “Snake Island” sequence], one of which had a very long lens. The cameraman’s got a tripod, and he’s got this incredible zoom, but he’s actually quite a long way away. He just needs a nice clear view through to where the action of the iguana is. He can zoom in; that’s his trick.

The other cameraman we had with a gimbal-type system, so he was shooting wider — you can’t be so stable with a long lens — but he was able to move around much more easily. When you’ve got a tripod, especially on sand, it’s hard to balance it.

Mike Gunton

So he’s the one tracking with the animals. That shot you see when the iguana first comes out, you’re tracking along, and then under the camera come those snakes; that’s shot on [the second] camera. Then all the details of the little looks, that’s shot on —

Elizabeth White

The long lens.

Mike Gunton

And by having two cameras, it allowed us to get the snakes’ perspective and the iguana’s perspective, all in one event. Normally you wouldn’t be able to do that; you’d have to piece it together.

“To be in the animals’ world, you have to be on their eye level”

Elizabeth White

A lot of people have thought the tracking shots were done by drone. But actually, virtually all the sequences shot on the animals’ level are done on a handheld unit. That was a real buzzword for us with this whole approach to the series: To be in the animals’ world, you have to be on their eye level. Otherwise, you feel kind of distinct or detached.

So for that cameraman with the tripod, that meant trying to get the tripod into the sand and get it as low as possible, and certainly for the handheld stuff it was about getting down as much as possible. But then the moment you lift up with a handheld device and you’re at human eye level, it looks like an aerial shot.

And that was great for us, because you can’t fly drones in the Galapagos. But someone said to me earlier, “Oh, man, how did you fly the drone?!” and I was like, “No ...”

It’s an amazing tool, to be able to use these smaller cameras and a stable system that’s handheld.

Mike Gunton

By taking it a lot farther away, you’re actually flattening the angle. On a tripod it’s quite hard to be at snake eye level, but if you’re 40 meters away, the angle effectively becomes so flat it appears that you’re at that level.

Caroline Framke

Well, I just want to watch this clip again now. And I’ve already seen it so many times.

Mike Gunton

[laughs] I reckon it’s going to be one of those clips film schools will analyze.

Caroline Framke

After watching such dramatic events, can you emotionally divorce yourself from what’s happening with the animals?

Elizabeth White

It can be hard, especially when you’re spending a lot of time [with them]. For me particularly, the penguin chicks ... you can see nice happy, healthy penguin chicks with these big bellies, and they look so content, and then you see a little penguin chick that’s almost like a tripod with its beak down to the ground; it’s just hollow.

And there’s a little part of you that wishes you could go down there and take all the little orphan ones and look after them. But we’re all biologists by background, and we know the reality is a lot of animals will not make it, and you can’t interfere.

Planet Earth II premieres Saturday, February 18, at 9 pm EST on BBC America.