The trick to being really dark is to control the scattering of light, says Sonke Johnsen of Duke University, in North Carolina, who studies the dragonfish.
The dragonfish emits red light from organs by its eyes, using an invisible headlight to locate unsuspecting prey that its scoops into its cavernous jaw.
Now, if we're really careful, then at the depth of 6, 600 ft, we'll be able to see the black dragonfish — a nightmarish creature that dwells in the deep and dark parts of the ocean.