RUPTURE, the fourth book in the Ari Thor thriller series to be published in the United States, continues Ragnar Jonasson’s pattern of combining traditional mystery elements and some unexpected twists with sharp, quirky characterization --- with the entirety highlighted by the exotic and frigid geographical backdrop of Iceland.

Ari Thor is part of a two-man police department tasked with policing a small Icelandic community outside of the larger and better known Reykjavik. Jonasson (assisted by the always fine translation of Quentin Bates) creates and maintains an air of deep melancholy that threads these books together. Ari’s personal life is as much of a factor in the series as the mysteries. In RUPTURE, he has reestablished a romantic relationship with Kristin, a doctor in Reykjavik, even as he faces (and sweats) the possibility that he has fathered a child with another woman during a short-term assignation while he and Kristin were apart.

"Ari’s presentation of his findings and deductions are worthy of an Agatha Christie novel in all of the best ways."

At the same time, the tiny village is under quarantine as the result of exposure to a deadly infectious disease from a visiting tourist. In the midst of all of this, Ari is asked to investigate the death of a woman that occurred a half-century before in an isolated, all-but-deserted village adjacent to his jurisdiction. It was originally ruled an accident --- death by ingestion of rat poison --- but was thought to have been a suicide. Ari has little to go on but a picture, at least initially. He follows that breadcrumb into a situation long undisturbed but still disturbing, and uncovers a secret --- with a vital clue discovered by Kristin --- that ultimately provides a dark, almost certain answer to the query, even if it is far too late for any justice to be done.

Ari’s presentation of his findings and deductions are worthy of an Agatha Christie novel in all of the best ways. But by no means is he the only protagonist in RUPTURE. A reporter who is looking into a child kidnapping unearths a crime of a different sort while doing research on her story, and also finds time to aid Ari in his own investigation.

Ari is quietly relentless, and while he may not be the sharpest hook in the fishing kit, he is certainly adept at putting the facts together and coming up with a reasonable conclusion, even with a case involving principals who have passed on long before. The ending indicates that Ari’s life is about to become more interesting, and Jonasson’s ever-growing body of readers will no doubt be on board for the next installment.