In the watery gloom 2,500 feet below the surface, a single tentacle unfurls to explore an illuminated camera.
What started as a solitary appendage is followed on-screen by a mass of undulating arms that tentatively probe the object before disappearing into the darkness.
Scientists have determined these arms belonged to a juvenile giant squid at least 10 feet long, the first one caught on camera in US waters.
The creatures are camera shy, mostly because they almost never leave the icy depths of their habitat, up to 3,300 feet, or about 1,000 meters, beneath the waves.
In 2012 scientists from Japan's National Museum of Nature and Science filmed a giant squid in its natural habitat nearly 3,000 feet down in the Ogasawara archipelago by using flashing lights to imitate other bioluminescent creatures of the deep.
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Three years later, the creature surfaced in the waters of Japan's Toyama Bay.
But these animals have never been spotted in the US — until now.
On June 19 researchers on a National Oceanic and Atmospheric Administration expedition captured a giant squid on camera in a stunning 25-second video in Gulf of Mexico waters 100 miles southeast of New Orleans.
"Even just a hundred miles off the coast, we're seeing things that they put on the corner of the maps — you know, 'Here lie monsters,'" Sönke Johnsen, a professor of biology at Duke University and the leader of the expedition, told The New York Times.
"You could be out here, and beneath you are giant squid, the things of our wildest imagination! They're part of our land, they're part of our country," he added.
This was only the second time scientists spotted the giant squid in its habitat beneath the waves.
The expedition team, which included researchers who helped capture the first deep-sea squid footage in 2012, used the same type of technology to lure the tentacled swimmer to their camera.
This camera system, called Medusa, sits on the end of a plastic line which the researchers spool and unspool with each deployment. Motorless, Medusa is quiet and doesn't scare away prey the squid might be hunting. It's also unobtrusive, using red light that's invisible to most deep-sea creatures but illuminates the scene for scientists on the surface.
The glowing lure, which the scientists nicknamed an e-jelly, entices the giant squid on-screen.
Most of what scientists know about these animals comes from carcasses that have washed ashore or have been found in the stomachs of squids' main predator, the sperm whale.
Squids have eight arms plus two long feeder tentacles that help pull prey from more than 30 feet away into its gaping maw. Each appendage is covered in sharp-toothed suckers that latch onto fish, jellyfish, other squid, and even whales.
These elusive denizens prefer to swim in deep water, their foot-wide dinner-plate-sized eyes enabling them to spot prey in near-lightless depths.
Giant squids are thought to swim in oceans nearly all over the world, based on the beaches where their carcasses have washed ashore. The largest one ever found weighed nearly a ton and spanned the length of two school buses from tip to tentacle.
This second deep-sea squid sighting is a major milestone for marine researchers who seek to dispel fear about these animals, which inspired the kraken, a legendary sea monster that attacked ships and pulled them to the depths, as well as science-fiction author Jules Verne's underwater behemoth.
"Most importantly, we did not find a monster," the NOAA scientists wrote in their expedition log. "The giant squid is large and certainly unusual from our human perspective, but if the video shows anything of the animal's character, it shows an animal surprised by its mistake, backing off after striking at something that at first must have seemed appealing but was obviously not food."
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