Lucy's friend Morag invites her on a paddle steamer trip through the Scottish lochs with her uncle, Captain Ming. Lucy is a special guest, for she once helped Kelpie, the magical water-horse. And though Morag doesn't believe in Kelpie and things like that, she does believe that Lucy will see the mermaid that Captain Ming loves, and be able to stop her from enticing Captain Ming away. This is a rich weave of fantasy and reality, with the reader - in true Mayne style - never quite sure where one ends and the other begins.
William Mayne was a British writer of children's fiction. Born in Hull, he was educated at the choir school attached to Canterbury Cathedral and his memories of that time contributed to his early books. He lived most of his life in North Yorkshire.
He was described as one of the outstanding children's authors of the 20th Century by the Oxford Companion to Children's Literature, and won the Carnegie Medal in 1957 for A Grass Rope and the Guardian Award in 1993 for Low Tide. He has written more than a hundred books, and is best known for his Choir School quartet comprising A Swarm in May, Choristers' Cake, Cathedral Wednesday and Words and Music, and his Earthfasts trilogy comprising Earthfasts, Cradlefasts and Candlefasts, an unusual evocation of the King Arthur legend.
A Swarm in May was filmed by the Children's Film Unit in 1983 and a five-part television series of Earthfasts was broadcast by the BBC in 1994.
William Mayne was imprisoned for two and a half years in 2004 after admitting to charges of child sexual abuse and was placed on the British sex offenders' register. His books were largely removed from shelves, and he died in disgrace in 2010.