The old salt farmers have always said that the violet scent of the Fleur de Sel at harvest time on the salt marshes of the Guérande Peninsula has been known to cause hallucinations. Commissaire Dupin also starts to believe this when he's attacked out of the blue in the salt works.

"Brittany's Guérande Peninsula is notoriously beautiful. The 'white country' between the raging Atlantic Ocean and idyllic rivers is a favorite vacation retreat for tourists and locals, including workaholic Commissaire Georges Dupin, who had actually been looking forward to escaping his endless paperwork and taking a trip to the salt marshes. But where the Commissaire goes, trouble seems to follow. Solitude quickly turns to suspicion when he finds himself under attack after snooping around on behalf of Lilou Breval, a journalist friend. Local salt farmers have always maintained that the violet scent of the fleur de sel, the famous salt produced only in Brittany, has been known to cause hallucinations. The explanation seems plausible, until Breval disappears without a trace. What's going on in the salt works? Thanks to his secretary, Nolwenn, and the ambition of the police prefect, Dupin is assigned to the case. But he won't be working alone this time: Sylvaine Rose is the investigator responsible for the Guérande--and she is none too pleased at having to share this case with Dupin. Together, he and Rose search feverishly for clues and stumble upon false alibis, massive conflicts of interest, personal feuds--and ancient Breton legends."--Dust jacket.