Xenophobic Delta Quadrant species that hides behind constant cloaking, so secretive that even its neighbors were unsure what it looked like.
The Ba'neth almost never allow themselves to be seen and keep their ships and stations cloaked. The neighboring Kesat knew of them mainly through attacks and rumor, and a Kesat investigator, Naroq, had spent years building theories about them.
In Riddles, a cloaked Ba'neth attacked Tuvok aboard the Delta Flyer, leaving him with severe neurological damage and a changed personality. As Neelix helped him recover, Tuvok recalled the cloaking frequency, letting Voyager expose a hidden Ba'neth station and obtain details of the weapon used on him.