The footage is peaceful at first. An autonomous vehicle shaped a bit like a torpedo, striped with yellow, green, and black, floats harmlessly through the gorgeous blue waters off Guadalupe Island. It hums quietly in the water, six cameras capturing the beautiful nothingness around it. Then, from nowhere, a white shark rises up into the frame. You see only its eyes at first, then the full effect of its massive body, tail switching back and forth. The shark pauses, eyes the vehicle, turns to its left, and dives back down. It's only gone a moment, though, before it comes speeding back up from the darkness, mouth wide open, and bites.

A few hundred feet up, on the boat, Amy Kukulya, Roger Stokey, and their crew are blown away. This is far beyond what anyone from the Woods Hole Oceanographic Institute had been hoping for. The organization is primarily dedicated to developing tools for and with other scientists, and Kukulya is a senior engineering technician, interested in underwater systems and especially in autonomous vehicles. But it's November, 2013, and the institute is working with the Discovery Channel ahead of Shark Week — and the crew in Guadalupe has just gotten footage unlike anything that's come before.

Kukulya and her team of engineers had been building up to this expedition for years, researching and improving autonomous vehicles to teach them to follow sharks. She'd trained them to follow boats, then to track a diver on a scooter flitting randomly around the ocean. "The idea," Kukulya tells me, "is you tag a shark with one of our navigation beacons, these transponders, and the vehicle's basically just interrogating every three seconds, and it's sending back three replies. The first ping gives it a bearing and a range, and then there's a slight delay, and a second ping comes back and gives it depth. And so the vehicle's able to triangulate its position, and know exactly in three-dimensional space where the shark is."

Tracking animals is far different from a boat, or even a person

This is how the ocean has long been explored, actually. "Back in the day UAVs were usually used for monotonous tasks: mow the lawn, find a needle in a haystack like a lost plane," Kukulya says. It works well for things sitting on the seafloor or for simple moving objects, like a boat on the surface. But the WHOI team has been trying to push the boundaries of both autonomy and power. "It becomes a more complicated math problem, essentially," she says. "So you tag a driver on a scooter and have him randomly drive around, and you see how quickly the vehicle can interrogate the transponder. Then you see how fast it can process that information, and [whether] it can stay close enough, but not too close, to whatever you're following to get the data that you need."

The power of the SharkCam is only partly in its hardware. The REMUS (which stands for Remote Environmental Monitoring Units) SharkCam weighs about 100 pounds, and has a range of 45 nautical miles. It's almost 7 feet long has six GoPros wrapped in a housing that lets them go down to 150 meters, along with navigational tools and the critical on-board computer that helps it track a great white. Really, it's the REMUS' algorithms that make these vehicles special.

A REMUS floats far underneath the surface. (WHOI)

The trip to Guadalupe with the Discovery Channel was only the second time the WHOI team had actually tagged and tracked real, live sharks. The first, in Cape Cod, was less than thrilling. Visibility was bad, and the sharks showed no interest at all in the vehicle. But as soon as the team went out on the water off the coast of Mexico, it was different. With 100 feet of visibility, they'd be able to see the shark swimming down to the edge of darkness. They could watch it hunt, watch it mate, watch it go about its day.

"We're throwing this really expensive vehicle in the water and trying to learn things on the fly."

They never imagined they'd watch it attack, though. "The cameras are on, and we're stressed," Kukulya says. "Everyone else is just hoping for the best, like, 'Okay I hope SharkCam gets some good footage.' And we're throwing this really expensive vehicle in the water and trying to learn things on the fly, and make it better on the fly." The vehicle was attacked their first trip out, as they tracked a different shark that had been tagged with a transponder. This happened over and over in Guadalupe, which has made Kukulya "think a little bit differently" about her next expedition. "We had no interest in losing this vehicle the second time we put it in the water."

Amy Kukulya (WHOI)

The expedition resulted in incredible footage for the Discovery Channel, which will air on Monday night as part of the show "Jaws Strikes Back." For Kukulya, though, it's more exciting for the questions it raised. "That opens up a whole suite of other questions for scientists and everything else to say well, 'What's the difference?' Obviously there's a different culture and a different diet and a different hunting technique." She's also more confident than ever in the vehicle's ability to track fast and randomly moving animals in the water, though she knows she won't always be as lucky as she was in Guadalupe. She's working on improving the battery life of the vehicle and its cameras, which currently work for three hours. "You just need to be in the water a lot longer."

This humming torpedo full of GoPros is going to help the WHOI study sharks, turtles, whales, and all manner of other animals. And Kukulya says scientists are already seeing the footage and asking her team to help them do more. She's excited to watch Shark Week, and to go back out with Remus, but she's already looking forward to exploring what she can't yet see.

"We're doing great things, and I'm hoping what comes out of this is more money to find ways to push down into even deeper depths."