Porth Tymestl, a small Southwestern Welsh coastal village in the early 1800s. John Kincarran, lost at sea. Lost in her own sea of grief, Ffion Kincarran curses the ocean beyond the graveyard walls. Inclement weather has caused the catch to decrease, causing Porth Tymestl to fall on hard times.

When bones wash up along a stretch of lonely shore, and a man with a strange name arrives like a sea-fret from beyond the horizon, brothers Eli and Tias, having lost their father, find themselves swept up in a world older than the foundations of the earth. With the help of the enigmatic innkeeper, Smythe, Eli and Tias are plunged into a world of myth, creatures from the deep and hunt for the truth behind the storms battering the coast, which may have been caused closer to home than they originally considered.

Do not be afraid; here there be monsters.