A bird sanctuary off the coast of Argyll is the setting for this new investigation by Chief Detective Inspector Colin Thane and Detective Inspector Phil Moss, sent north from the grime and urban decay of Glasgow to the remote and lovely island where the local bird warden has been found murdered.

In this wonderful haven, now tainted by the killing, the detectives encounter two kinds of danger - one human, in the shape of their quarry, who becomes more desperate the closer they come, and the other natural, a line of half-tide rocks known as The Fangs, greatly to be feared by anyone unfortunate enough to be stranded near them.

Then the detectives are given an enigmatic clue involving the figure one thousand, five hundred and eighty-eight - but it's only when they make a date with history and realize that the allure of buried treasure might lead to murder, that the mystery can finally be resolved.