An ancient horror, dormant for centuries, awakens when an uncharted village is discovered under the sea off the Suffolk coast. Identified as Southmere, the village was lost to the waves over five hundred years ago and never rebuilt, with only the woodland atop the cliff retaining its name. However, a single, ancient map reveals the village’s true name: Twinmere.

As a campaign to restore the original name gains traction, a retired priest is filled with dread, knowing the horrors that will be unleashed if the name is changed. Desperate to warn the public, he finds himself unable to reveal the true reason behind his fears, and his warnings are dismissed as the ravings of a senile old man.

Now, with the campaign to change the name gathering momentum, the priest must find a way to stop the impending doom before the ancient evil is unleashed upon the world once more.