Deep One

The Deep Ones are creatures in the Cthulhu Mythos of H. P. Lovecraft. The beings first appeared in Lovecraft's novella "The Shadow Over Innsmouth" (1931), but were already hinted at in the early short story "Dagon". The Deep Ones are a race of intelligent ocean-dwelling creatures, approximately human-shaped but with a fishy, froggy appearance. They regularly mate with humans along the coast, creating societies of hybrids.

Numerous Mythos elements are associated with the Deep Ones, including the legendary town of Innsmouth, the undersea city of Y'ha-nthlei, the Esoteric Order of Dagon, and the beings known as Father Dagon and Mother Hydra. After their debut in Lovecraft's tale, the sea-dwelling creatures resurfaced in the works of other authors, especially August Derleth.

Lovecraft provides a description of the Deep Ones in "The Shadow Over Innsmouth":

I think their predominant color was a greyish-green, though they had white bellies. They were mostly shiny and slippery, but the ridges of their backs were scaly. Their forms vaguely suggested the anthropoid, while their heads were the heads of fish, with prodigious bulging eyes that never closed. At the sides of their necks were palpitating gills, and their long paws were webbed. They hopped irregularly, sometimes on two legs and sometimes on four. I was somehow glad that they had no more than four limbs. Their croaking, baying voices, clearly used for articulate speech, held all the dark shades of expression which their staring faces lacked ... They were the blasphemous fish-frogs of the nameless design - living and horrible.

Lovecraft describes the Deep Ones as a race of undersea-dwelling humanoids whose preferred habitat is deep in the ocean (hence their name). However, despite being primarily marine creatures, they can come to the surface, and can survive on land for extended periods of time. All Deep Ones are immortal; none die except by accident or violence. They are said to serve the beings known as Father Dagon and Mother Hydra, as well as Cthulhu. They are opposed by mysterious beings known as the Old Gods, whose powerful magic can keep them in check. This detail is one of the vestigial hints that August Derleth developed as the mostly unnamed Elder Gods.

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