The story begins when Ulf, aboard his yacht the Rustica, is handed a ship's log by a sailor who then disappears. The log tells of the rescue of young woman who was to be ritually killed in a Druidical sacrifice. This and her apparent re-abduction lead Ulf and his friend Torben to make a dangerous winter crossing of the North Sea, in an attempt to save the woman and find out more about her captors. A black fishing boat, the F154, seems to turn up wherever they go, and finally McDuff, its skipper, warns them off. Ulf and Torben piece together evidence that a secretive organization, the Celtic Ring, bent on creating an independent Celtic federation, is involved. The remainder becomes a cat-and-mouse game between Ulf and Torben, McDuff, and his less gentlemanly Celtic Circle associates, ranging down the lochs, canals and treacherous shores and islands off the coast of Scotland.

While the premise of a Celtic conspiracy might be somewhat implausible, particularly given the heightened autonomy recently given to Scotland and Wales, the well-developed intrigue and mystery in The Celtic Ring more than makes up for it. The heroes, while cultured and accustomed to a certain standard of living, are both interesting characters; Ulf very stoic, self-sufficient and structured in his life, Torben much more emotional and prone to impulsive decisions. In many ways they and their foes, along with the slow but steady development of the story, are very reminiscent of the novels of "clubland heroes" of John Buchan (Richard Hannay) or Dornford Yates (Chandos et al.).

Lastly, if you're worried that you won't understand all the sailing jargon, don't worry. As someone who knows absolutely nothing about sailing, I had no difficulty with The Celtic Ring. This isn't to say, however, that if you are a sailing enthusiast you won't get a great deal more out of the book, but either way it will become evident to you that the author is someone who is truly passionate about sailing and the sea. This, in and of itself, is worth the price of admission.