The footage was captured by MBARI Senior Scientist Bruce Robison while controlling the remotely operated vehicle Doc Ricketts in Monterey Bay. The 9cm-long anglerfish is swimming around at a depth of 580 meters (1,900 feet), and due to the species this is identified as a female complete with fishing pole (the males don’t have them).
As the video explains, this is an ambush predator.
It is not built for speed, instead using the light at the end of its fishing pole to attract fish and squids within range to be sucked into that huge mouth. This example is also an easy one to identify if seen again due to the broken tooth hanging out of its mouth (presuming it doesn’t fall off).