Secretive North Korea is not an obvious choice as the location for a detective story, not least because it is so impenetrable to the outsider.

But Asia specialists say this novel offers a vivid window into the mysterious country.

One expert called it “the best unclassified account of how North Korea works and why it has survived all these years.”

The protagonist is Inspector O, whose investigation into a murder at the Koryo Hotel pitches him into a deadly contest between powerful factions in the regime.

The nation’s leader is never mentioned by name, but his shadow stalks every chapter. The inspector is a man struggling to hold on to his humanity in a world where humanity has little value.

The depth of detail is perhaps less surprising when you learn that James Church is the nom de plume of a former Western intelligence officer who spent years in Korea.

But it more than justifies the verdict of Newt Gingrich, the former Republican US presidential hopeful, who declared the book “a must-read” for anyone trying to understand the Kim dynasty of dictators.

This truly original thriller is about much more than a crime investigation.