Ever since Dr Rose was a little girl paddling in rock pools, she has always loved the sea and exploring the weird and wonderful creatures living there. Now, as a marine biologist, Dr Rose is in search of a sea creature rumoured to reside within its hidden depths; one that many speak of, but no one has ever seen – Carmella. With her team of scientists and explorers, she will descend to the unfathomable dark of the deep ocean in a slick submersible, to discover the incredible, and almost unbelievable, creatures that inhabit a nearly pitch-black world.