The Snow Goose takes place in the marshes of Essex, in southeast England. A hunchback, Rhayader, lives a hermit-like existence in an abandoned lighthouse, with nothing for company but flocks of wild birds, paint brushes and his small sailing boat.

Then one day a timid young girl appears hesitantly at his door. Her name is Frith. She is fearful of the misshapen Rhayader...

But greater than her fear was the need of that which she bore. For locked in her child’s heart was the knowledge, picked up somewhere in the swampland, that this ogre who lived in the lighthouse had magic that could heal injured things.

It is an injured snow goose that she brings, in the hope that he can help it. He does, and they become a companionable trio. But when the goose migrates north, Frith vanishes. It is not until the snow goose returns in the autumn that Frith becomes a regular visitor at the lighthouse again. The migratory pattern repeats itself season after season.

Frith begins to see Rhayader for his true self, to see beyond his deformities, as she approaches womanhood. But then the call goes out for boats to rush to the aid of allied soldiers trapped at Dunkirk. Rhayader sails his little boat across the channel to help evacuate the forces. As he departs, the snow goose takes flight and follows him.

Through his brave efforts, countless men are rescued. Meanwhile Frith awaits him at the lighthouse. But, alas, the snow goose returns alone.