At Grannie Island's ceilidh, Uncle Matthew tells a story about a teenage girl called Annie Jessie who lived on Struay long ago. She works hard looking after her family. One day when sheltering from a storm she meets a merboy who has lost his comb. Annie Jessie makes him a new comb from a razor shell and soon they fall in love. With the help of the sea king, who is in charge of all the creatures of the sea, they are able to go and live happily together on the island of Fuay.