The Tide Turner by Angela McAllisterRobin: The Tide Turner creates a truly believable underwater world. The mer people here are called Delphines; they have smooth tails like dolphins and must occasionally take a breath of surface air. There are different groups of Delphines, including Silvertails who farm the sea bed, and Bloodfin hunters from the cold waters of the North. The Delphines refer to humans as “Crawlers” and are rather fascinated by the human artefacts which fall into the sea. They live in “pods”, small family-based settlements, although there are also some loners and nomads. They have legends about the Merrows, guardians of the sea under the auspices of the Sea Spirit, who are believed to be no more.

Cal, a Silvertail girl, is investigating the mysterious disappearance of her mother when she meets Jake, a sea foundling who has just lost his human foster parents. When a sudden sea fury wrecks Jake’s boat, he is amazed to find that he can survive underwater, and communicate in Cal’s strange language. This mystery is gradually unravelled, and the pair become closer as they try to outwit the fierce Bloodfin.

The enigmatic outsiders, Orcara the witch-like healer, and Tarian the trader with a dangerous pet octopus, both help Cal and Jake at times – but whether they are true allies only time (and perhaps tide) will tell. Skimmer, the giant manta ray who comes at Cal’s call is perhaps my favourite character.

The underwater geography is convincingly described, and the map on the inside cover adds interest. The cover itself is rather clever – though at first sight a simple picture of blue-green weed and fish against black ocean, at a certain angle a beautiful face can be seen imprinted on the black, perhaps the Sea Spirit herself. (It is no use squinting at the picture here – you will have to look at the actual book)