Arthur rescues the elderly Aulfric and his pretty daughter Sophia from being robbed and welcomes them at Camelot. Indeed Arthur falls in love with Sophia and they plan to elope. Morgana is very worried as she has had a recurring dream in which Sophia drowns Arthur. She confides in Gaius and Merlin, who realize that she is a potential sorceress with the power of prophecy. Merlin follows Aulfric to a lake, where he discovers that the father and daughter are Sidhes, former immortals who, having lost their immortality, must kill Arthur to regain their powers. When Sophia …
Watch It Here : Merlin Season 1 Episode 7