In a small town on the Celtic coast, an ancient legend haunts the lives of the inhabitants. Young men are disappearing at sea. Some see it as the work of the devil, others blame a sea creature from the ancient world. All the clues seem to lead back to the city of Ys. Léon and his friends decide to investigate, even if it means descending to the depths of the abyss.

Bethan Siân
as Princess Dahut

Talwyn Baudu
as Léon

Azenor Kallag
as Sara

Elfed Wyn Jones
as Cador

Nely Van Seventer
as Itron Glenmor

Beca Tredomen
as Hen Helen

James T. Owen
as The little boy

Simon Lovatt
as The ghost

Donald Sinclair
as The sailor

Rhisiart Hincks
as Tom Glenmor