Extreme diver Norbert Wu's Journey into the Antarctic underworld: Showing a medusa or jelly (Desmonema glaciale). It lives near the surface and the bell can reach over one meter in diameter. It is incredibly intricate and beautiful though.
“What we see before us is just one tiny part of the world. We get in the habit of thinking, this is the world, but that's not true at all. The real world is a much darker and deeper place than this, and much of it is occupied by jellyfish and things.” ― Haruki Murakami