Strange beings lurk in the deep sea. Weird life, unlike anything found near the ocean’s surface, and bizarre enough to make anything lucky enough to be dwelling on land spit out its morning coffee in disgust.

A pretty high proportion of this deepwater life glows. In areas of the ocean termed ‘mesopelagic’ (between 500 and 1,000m deep) there are no obstacles to hide behind, no floor to hide on, and yet some weak downwelling sunlight ensuring that complex beings need to retain some level of vision to survive. This combination of characteristics makes bioluminescence a particularly valuable tool, both for concealment, communication and combat. All known bioluminescence is either produced by bacteria housed within the animal in question, or produced by specialised organelles of the animal itself.