This darling denizen of the deep is a Helicocranchia, aka a piglet squid. Scientists on the Ocean Exploration Trust's E/V Nautilus caught footage of the rarely seen creature at a depth of 4,544 feet near Palmyra Atoll in the Northern Pacific Ocean. The commenters' delightful descriptions really make the clip.
Delightful deepsea encounter with a wildly cute and weird piglet squid