H.P. Lovecraft's The Shadow over Innsmouth: Cthulhu Mythos

The Shadow over Innsmouth is a horror novella by American author H.P. Lovecraft, written in November-December 1931. It forms part of the Cthulhu Mythos, using its motif of a malign undersea civilization, and references several shared elements of the mythos, including place names, mythical creatures, and invocations.

The Shadow over Innsmouth is the only Lovecraft story that was published in book form during his lifetime.