Roanne is to spend the summer with an uncle she has never seen, who lives on a desert island. The man is very strange, even frightening. The mysterious shipwrecks that have occurred in the area do little to reassure the young girl, who can't wait to leave. Then she discovers her uncle's secret... With its extraordinary underwater adventures, its evocation of the environmental damage caused by human activity and, above all, its reflections on self-acceptance and acceptance of others, the novel has many facets. The richness of the marine world created by the author is fabulous, and the characters, especially the grumpy uncle, are truly endearing. We move from mystery to adventure, with a touch of humour, and a fine demonstration of the need to have a family, in the broadest sense of the term, and to help each other. A captivating and profound read.