The most terrifying sequence of 'Blue Planet II,' the Bobbit worm, airs this weekend

Mandi Bierly

Each episode of BBC America’s Planet Earth: Blue Planet II takes viewers through a myriad of emotions, and this Saturday’s installment, “Coral Reefs,” is no different. There’s joy (adolescent bottlenose dolphins playing a game with broken pieces of coral in the Red Sea), and there’s wonder (an octopus and a grouper buddy up to hunt more effectively in Australia’s Great Barrier Reef). But there’s also stress. Prepare yourselves for the Bobbit.

As narrator Sir David Attenborough explains, it’s “a giant carnivorous worm with jaws as sharp as daggers” that burrows in the sand and waits (like the creatures in Tremors) to pop up and snatch unsuspecting fish. You’ll have to tune in Feb. 3 to see the full sequence, which begins with a meter-long Bobbit (yes, named after those Bobbitts) doing some night stalking that flat-out traumatized U.K. viewers when the episode aired in Britain last November. When our sneak peek picks up, it’s dawn, and the tiny foraging bream fish that were such easy prey in the dark now have the advantage since they can spot the Bobbit. In fact, they actually join together to blow away the sand and expose it — at least temporarily. Warning: This clip will make you jump (wait for it).

“Reefs are the cities of the sea. They occupy such a tiny part of the ocean floor, yet house a quarter of all [ocean] species. They really are these vibrant metropolises, and, like in any city, around every corner there could be great opportunity, but there also could be great danger,” episode producer Jonathan Smith tells Yahoo Entertainment. He knew about the Bobbit’s hunting technique, but what persuaded him to include it in the episode was a conversation with a scientist, Jose Lachat, who told him he’d also observed bream mobbing a Bobbit to reveal its hiding place. “That was the ultimate for me. I’ve heard people explaining this story and they’re giving a spoiler alert,” Smith says. “There are so many twists and turns through it that it’s the perfect story.”

What he loves most about the sequence, really, is that it turned out to be nearly impossible to film. “We’d been sent pictures of Bobbits at night, hunting, with normal light on them, and they seemed fine. We got there and then [cameraman Hugh Miller] found a good Bobbit worm, set up his studio, went down at night — bear in mind he’s like a meter away from this Bobbit worm, sitting there and waiting — but the Bobbit was too scared to do anything under the white light,” Smith says. “Luckily, he has been the only person in the world to have built an infrared lighting system for underwater. The problem with infrared underwater is that it attenuates incredibly quickly through the water column, so you just lose it, so you can’t really light much of an area. But he’d found a slightly different wavelength that enabled him to film at night in complete darkness, but still be able to capture imagery on this camera. And it just so happened he had taken that out to test it in the field. So suddenly everything changed: We went, ‘This is how we have to do the Bobbit,’ and that’s why the Bobbit sequence is the color that it is. It actually, I think, really gives that added element of horror to it. Hugh, creative genius, managed to capture and give an incredibly unique insight into this dark world of the reef.”

Smith has another favorite sequence — clownfish on the more barren outskirts of reef city pushing objects toward their anemone, to give the female something solid to lay her eggs on — that he loves because it too seemed impossible when he first heard about it. At the beginning of production, he reached out to Roger Munns, a cameraman based in Borneo who’s spent decades filming and learning about the reefs there, to ask for the best stories he’s heard. “He was saying a couple of stories, and then he said, ‘But you know what, I’ve heard about this story over 10 years ago, where there’s a clownfish that will go out and collect things and push them to its anemone.’ And I thought, ‘Wow, this sounds like a brilliant story,’ but he had never seen it. We couldn’t find any pictures of it. There’s certainly no video of it. But it seemed so intriguing, we had to try and find out more,” Smith says.

The series’ researchers dug in and found one mention of the behavior from the late 1970s, but that was it. “So again, we reached out to the world, and there was a scientist in Papua New Guinea — you kind of feel like Sherlock Holmes when you think about the incredible size of this stuff,” Smith says with a laugh. “But he told us this extraordinary story. He’d been studying these clownfish in Papua New Guinea and measuring how many eggs that they make. In order to do this, he would take them this lovely shiny tile, something nice and solid and perfect, exactly what he figured they’d need. He went down to one family of clownfish, and — it’s so strange — they had tucked into their anemone a baby doll arm that had obviously drifted by somehow. And so he goes, ‘OK, it’s a bit of rubbish,’ and he picked that out and discarded it, and then just put it to the side of the reef because he wanted whatever’s been living on it to still be OK. Then he put his tile under the anemone. When he came back a few days or a week later, expecting to find this tile covered in clownfish eggs, instead the tile was three meters away from the anemone. It had been completely shoved out. And sitting back under the anemone was the baby doll’s arm, covered in clownfish eggs. He sent us these pictures, so that was another part of why we thought, ‘Right, this certainly happened, so now we’ve just got to find the right clownfish and we’ve just got to sit there and wait and watch.'”

And that’s exactly what he and Munns did in Borneo — for probably about 100 hours, Smith estimates, before they finally started getting shots of the clownfish investigating and trying to move various objects that came nearby. Did the men ever think about giving up? “There are so, so many times, obviously, where you’re sitting there and thinking, ‘How are we ever going to manage it?’ And it’s even more so when you go into something slightly blind,” Smith says. “You know that logic tells you it should happen, but having never seen any film of it you’ve still got that slight [feeling of], ‘Are we completely wasting our time?’ But all of that makes the moment when it happens even more amazing.”

Marbled grouper make their move to mate, with grey reef sharks waiting to strike. (Image: BBC America)
Marbled grouper make their move to mate, with grey reef sharks waiting to strike. (Image: BBC America)

Another high-risk sequence, which is featured in the “making of” segment at the end of the episode: marbled grouper waiting en masse for the precise moment they’ll swim upwards, females dropping eggs and males releasing sperm, in the hopes of giving their fertilized eggs a chance to be swept out with the tide. Why is it so dramatic? The hundreds of hungry grey reef sharks waiting above to swarm the grouper, and also because the grouper only spawn once a year, and the event lasts for just an hour — not great odds for a camera crew.

“If I know that in my hour-long film I can give you maybe 10 stories that describe what the coral reefs of our planet are, then I need to really pick and choose those stories carefully,” Smith says. “And there’s a couple of parts of this story that I really felt we needed to know to understand the bigger picture of the reef. And one of them is the fact that almost every animal on the reef has the same basic mating strategy, which is to get their eggs as far away from the reef as they can. And it kind of doesn’t make sense, because actually, out there away from the reef is the big blue world with little nutrients and little to offer, whereas the reef is this vibrant metropolis. But [it’s about] making it to the top of the reef city — we have to rise to the top — and if you’re a little baby, you’re a little egg, you can’t do that yet. You’re not ready. And ultimately, it’s because the reef is so competitive that everything throws its young away — but then they come and they resettle. And in that going and drifting and then resettling, that enables reefs to colonize new worlds, and ultimately gives us some hope in this changing world that reefs [which are being bleached by rising temperatures] can keep continuing into the future, because of this ability to adapt, which is all driven by the competition and the need to get to the top of the reef city. So I wanted to share that element. And then I thought, ‘Right, what’s the most amazing way we can possibly show that?’ And we thought 30,000 grouper, caught in the seabed of a channel in French Polynesia that’s patrolled by 500 grey reef sharks. That to me was a story that we had to try and do.”

Planet Earth: Blue Planet II airs Saturdays at 9 p.m. on BBC America.

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