Commissaries Dupin leads a team investigating drowning deaths on the Glénan islands located off the coast of Brittany. Actually, the setting is one of the most interesting things about this mystery. I don‘t know whether it is the fault of the author or the translator, but the language is pretty stilted, and at times flat out awkward. Also really annoying are the excessive typos, sometimes over three per page: unforgivable in the first US edition!