Based on H.P. Lovecraft's short story, a man finds himself struggling to survive an encounter with the god of the sea and his mutating fish-like followers. After a boating accident during a yacht trip, young couple Paul (Ezra Godden) and Barbara (Raquel Meroño) end up stranded on an island inhabited by the people of a small fishing village. Soon, Paul finds himself separated from Barbara, and running from the entire town, fearing for his life and for her safety. Dagon is a god who insists on human sacrifices, and the townspeople must provide.
UK version includes "The Making of" and the theatrical trailer.