León, a curious little boy, is on holidays in his grandmother’s house in Ireland. There he meets Seán the leprechaun, who has a crock of gold.

Seán goes to Madrid with León and meets Witchy, the cat, and Eala, the swan. Together they have many adventures, for example, The Battle of the Vaguada.  Seán needs a place for his crock of gold so they paint the arches the colours of the rainbow. As well as painting them, they splash each other with the different colours and have great fun.