Five-year-old Kim lives near Manchester with her mother and brother Victor, aged 10. Kim believes in the story that there is a pot of gold at the end of the rainbow.
One day she follows a rainbow to its end and discovers the truth of this story - and also meets Paul, who lives in a little house at the end of the rainbow.
When Kim and Victor go to stay with their mother's aunt in Skegness, a seaside town on England's east coast, Kim meets Paul again. This meeting, together with Paul's memories of something much further back in his past, lead to a discovery which may change all their lives.